Episode 9 of the anime had a small moment where Kurumu offers to carry Yukari back to camp after she'd been injured. Yukari's okay thanks to her Healing Factor though, so she walks off by herself, leaving Kurumu to run after her and shout at her not to exert herself.
In general, any time the girls get friendship moments with each other, since in much of their downtime they're romantic rivals.
Manga: Season I
T'was the week before Tsukune's 16th birthday. He was hoping to spend it with Moka. She, on the other hand, was spending the week modeling for an art class. As the days pass by and Tsukune keeps missing chances of asking her to be with him, he grows increasingly frustrated and ends up almost dying (again). He wakes up in a hospital bed on the day of his birthday, thinking Moka had forgotten it and feeling quite down. And then Moka proudly reveals the drawing she'd spent the past week on. The theme was "something important to you". The drawing is of Tsukune. And to top it off she tells him she loves him.
Chapter 7. Kurumu fights to protect her friends and their newspaper work from the slug monster, showing how she truly cares for them, and unlocks her illusion powers in the process.
Chapter 26. Moka has been having doubts, avoiding the others, and thinking about leaving the school. Kurumu takes her somewhere to meet in private after some not-so-subtle threats from Kiria. There, first she tries to remove Moka's rosary herself, concerned about her running into Kiria. When that fails, she expresses her frustration over how Moka is acting and tells her to leave. As Moka walks away in tears, Kiria shows up and chastises Kurumu for driving her away from him. He then sics a pair of cyclopses on Moka to try and draw out her vampire side. He holds back Kurumu, hinting at how this will leave Tsukune open for her. She stands there a moment looking at Moka, then turns her head away. Then, just as one of the cyclopses has Moka cornered, jumps in to slice him in the face. She calls out Kiria on his enjoyment over the whole thingnote Fridge Brilliance: when she turned her head, she was looking at Kiria and seeing his expression and says her heart won't change so easily. Then, Moka stands up, ignoring Kurumu's order to run, and stands with her to fight. They exchange a few comments about sticking together, smile, and then proceed to kick ass.
Preceding the above was Kurumu going to Moka's apartment. When confronting her on avoiding Tsukune and her friends, Kurumu asks Moka that if she is so dead set on avoiding Tsukune, why didn't she leave the school...
Moka: "He asked me not to…"
The aftermath of the fight. There's something awesome and very satisfying about seeing them lounging around on the backs of their defeated enemies, reaffirming their friendship.
During the school festival both Mizore and Kurumu had told their mothers that Tsukune is their boyfriend. He was set to have lunch with both families, neither of which knew of the other one. All he wanted to do was walk around with Moka. The heartwarming came from Mizore who, upon realizing what Tsukune's wish was, made ice clones of him and sent them to meet the mothers, while the real Tsukune went with Moka.
Chapter 34 of season 1. After everything that Hokuto has done, Tsukune still believes that Hokuto's wish to make the school peaceful was genuine. It's enough to move Hokuto to help sabotage his own plan.
That is however, slightly spoiled with recent events which imply a Kira-esque plot on Hokuto's part.
The scene in season 2 of the manga where Mizore tries to commit suicide by jumping out of some odd-story-high castle window after being essential sold off into an arranged marriage and Kurumu flies out of the window after her. As Mizore weeps as she felt violated by her new 'husband', who had kissed her against her will, Kurumu cuts her off by kissing her, tearfully asking "A kiss isn't so bad, is it?" all the while drifting down to earth. Sure, Kurumu threw in some tongue but considering their frienemy status, it's very awww-inducing indeed.
Easily Kurumu's Crowning Moment of Awesome and massive Tear Jerker, all rolled into one spectacular scene. The normally emotionally-restrained Mizore is absolutely hysterical screaming "He touched me everywhere, I didn't have time to resist. Scared... I was so scared!" about her sexual assault (The only thing he did not do was physically rape her.). Mizore thinks that she is ruined forever, when Kurumu kisses her, she does absolutely the one thing to convince her that yes, someone will want to kiss her again. At which point Mizori breaks down entirely, crying like a baby in Kurumu's arms, who holds her and tells her everything is ok now.
And as for the tongue part, Kurumu is a succubus after all; it probably comes naturally.
Gin trying to calm down Kurumu as she talks to him about her reciprocated feelings for Tsukune. You can really say he puts the "Chivalrous" In Chivalrous Pervert if he can use the same line he tried to use when he was in bed with her to reassure her that everything's going to be alright.
The scene where Sun's adoptive human mother is able to look past her hatred and prejudice. Sun is found to be a siren, and a siren killed the woman's husband, but she embraces Sun and reassures her that she is her daughter.
Why did Tsukune and the harem help Sun? Because they believe that Sun and her adoptive mother are a representation of the dream of a peaceful world between monster and humans. True Companions at its finest.
 Make sure no one else can hear your AWWWWWWWWW!
In Inner-Moka's spotlight chapter in which she decides to go to school for a day, she ends up becoming depressed when she realizes that she is a Lethal Chef. Initially the story implies it to be a Break the Haughty moment, but then it's revealed that she's actually depressed because she wanted to cook something to impress Tsukune. Despite the fact that her food looked horrible, Tsukune ate it anyway and complimented her on how good it was regardless. Her reaction? Just look at the picture on Defrosting Ice Queen.
When Fang Fang finally takes the crew into his family estate, he seems way more cheerful than he usually was. As it turns out, he'd never had friends before because of his position as heir. Noticeably after this reveal, Tsukune is a lot nicer to Fang Fang.
Ling-Ling's farewell speech to her younger brother before trying to take down Akuha
Also, "I'll fight. There's no way I'll let him lay another hand on anyone!"
Chapter 48 of season 2 features Yukari's heartwarming statements to Fong-Fong. He was excited to see her and thanked her for coming to his aid against Xilong, but she turns the whole thing around and admits that he saved her with his then unrealized martial ars ability with a Luminescent Blush on her face.
A subtle one in chapter 33. Akasha tells Alucard that she won't permit him to take away her beloved daughters. Plural. Right after Akuha attempted to kill her.
Chapter 53, when Kurumu reflects on her friendship with Moka.
In truth, there were so many times when I thought, "If only I could hate you. If only I could hate you. If only I could hate you. I thought that so many, many times... It's strange, isn't it? I'd thought that living for love was everything to me, and yet...
Chapter 54: "All this time I've been chasing and chasing, and I've finally come this far. This time, it's my turn to protect you."
Tsukune catching Inner Moka in an embrace saying that protecting isn't the only thing connecting her to him. And to top it all of? Inner Moka tearfully crying out his name and returning the embrace. Awwww.... It truly shows how much her cold charade has fallen apart.
Chapter 50, When Miyabi offers the group to be taken straight to Moka and Mizore cowers behind Tsukune at the sight of him. Tsukune refuses.
Tsukune: No... I appreciate the offer, but I'm still going to have to refuse...!
Tsukune: You should know why... you haven't forgotten, have you? What you did back then, not only did you invade Mizore-chan's village, you even forced yourself on Mizore-chan... I cannot forgive you. So there is no way I can trust you.
"It's calling me. It's calling me... Who is it...?... I'm losing consciousness... I don't hear anything. Soon, I'll lose everthing else... Isn't that... Moka-san? When I die, if I can hear your voice, I wouldn't have any regrets. Can I be your most important person? With these hands can I even protect you? Tell me... can you smile at me right now, it's the only thing I desire."
After defeating Gyokuro in a massive slug-fest, Tsukune's condition starts to deteriorate and is knocked unconscious from the heavy damage he took. He slowly falls down as a tearful Inner Moka runs after him and catches him. And before that was Moka crying out his name begging him to stop. OH MY GOD!! The Ship Tease is breaking my heart apart!
the End of Volume Theater for Volume 8 of the second manga season gives us this yes the family may be messed up in several hundred directions and ways especially now but the sisters really do respect and love each other and always have.
Chapter 61. At the start of chapter Moka is seen hugging Tsukune who previously passed out after fighting Gyokuro. As he lies unconscious she tearfully begs him to wake up.
Moka: Don't die Tsukune! You aren't allowed to die!
Chapter 62. Everyone stepping in to fight Moka's challengers so she can go beat Gyokuro. Kurumu and Mizore take on Kahlua, despite their injuries. Yukari and Fang-Fang declare "unfinished business" with Gairen, who dropped a ceiling on them earlier. And Moka is moved to tears at how they've all been looking out for her.
Chapter 66. Tsukune and Moka finally confess to each other and kiss. Crosses with Tear Jerker since Moka is dying.
66-3. Akuha attempts to heal Moka by injecting her own blood. Unfortunately, it's not enough. Tsukune ends up discarding his humanity to save Moka. The kicker: his words echo the last words Jasmine said to her before she turned herself in to the mob who lynched her.
Jasmine: Human, creature, none of that matters to me...! I want to believe in something much more valuable.
Tsukune: Humans, creatures, really, I don't care about any of that. Nothing is more important to me than the one I love.
66-4. Inspired by Tsukune, Akuha forms a magic circle so that she and the rest of Moka and Tsukune's friends can help Tsukune by sending him energy and teaching him to control his powers.
Thank you...we heard all of you...loud and clear.
Alucard confronts Tsukune with the fact that he's not human anymore and reveals that he's planted "eggs" which are hatching and unleashing clones of him all over the world. Tsukune's response is to point out that it doesn't matter whether or not he's human or monster, that he still wishes for humanity and monsters to coexist peacefully. And to further prove Tsukune's point, The Miu and Wong Families and some of the students and staff from Yokai Academy (including former ANTI-THESIS members), the mothers, and possibly other monsters are helping to defeat Alucard's clones.]
It turns out even Alucard at one point believed that humans and monsters could coexist peacefully.
In the end, it turns out that Miyabi/Alucard was able to save Kahlua before she died. He gives her to Kuyo to have her recuperate, then states something about how out of everyone, she didn't deserve to die yet.
The epilogue shows us that Gin went to work at San's hotel after graduation. And unlike him in any other situation with a girl, both parties are terribly and adorably shy around one another.