The Lights learning the "unknown feeling" is love at the end of Episode 1.
Mega Man and ProtoMan's conversation in the park in Episode 5.
A lot of episode 6's moments with Kalinka and Mega Man, particularly their first kiss.
Lynn saving her brother, Castor, against all odds.
ProtoMan calming down a Met that Wily had tortured and letting it escape with Roll.
Roll's interactions with Mets.
Roll meeting Captain Fallout and the Atom Smashers, her favorite band, and getting their autographs, sunglasses, and a guitar. Becomes meta when you learn the author based it on the interactions The Protomen have with fans.
Roll naming the Met Peekaboo.
Tron's interactions with Servbots.
ProtoMan letting the female RM go and lying to Wily about it.
Drill Man's redemption in Episode 8.
Roll showing Peekaboo Doc's tree. Boo thanks him for saving Roll, and at that moment a gentle breeze picks up.
In Episode 9, upon hearing ProtoMan being attacked by Bass, Mega Man was willing to drop everything to rescue him in spite of everything he'd done. Their conversation immediately beforehand was sweet, too.
Similarly, ProtoMan not wanting the police to get slaughtered by Bass.
Episode 9's initial battle with Galaxy Man has Mega pulling out all the stops to save his family even at the expense of his own energy.
The interlude to Episode 10 had Mega and Roll calming down Peekaboo after he was scared of an incoming soccer ball. Roll even pointed out that he made a good goalie.
Mega Man's preparation for his date with Kalinka in Episode 10.
In the same chapter, Roll mentioning Doc as an angel watching over them when Kalinka compares Peekaboo to an angel.
Mega Man's actual date with Kalinka in Episode 10. This includes both of them saying that they like each other for who they are inside; as Mega confesses that he fears Kalinka won't like him after the war with Wily is over, and worries that people see him as only Mega Man and not Rock, she affirms that she always will.
Because he trusted her with his feelings, she decided to help make him feel better by making a request. "I know you have to keep armor on, but... please, take off your helmet," she requests. Mega looks surprised at first, but Kalinka explains, "Tonight, you do not have to be Mega Man... we're just two friends named Rock and Kalinka tonight."
Then they almost kiss.
Episode 10 has ProtoMan meeting with Nomad and helping her out; the narration comments that he feels a true sense of purpose for the first time.
It's doubly heartwarming in that he entrusted Cut Man, Guts Man, and Magnet Man with the secret.
Episode 10 has even more heartwarming with Mega and Kalinka confessing their doubts and insecurities to each other, Kalinka placing flowers at Doc's tree, and Roll being informed of some of the good things ProtoMan's done.
The second conversation between ProtoMan and Mega Man in episode 10. Proto comes clean about manipulating Mega, apologizes to him for doing so, and tells him about Project G-2, the Mega Man Killers' weaknesses, and even offers a tip about Bass.
Mega Man and Kalinka's second kiss.
The climax of episode 10 has Roll staying home with Peekaboo to ensure he feels protected, trusting Mega Man to save Kalinka.
Mega Man and ProtoMan avoiding a conflict to save an innocent girl caught up in the carnage. It becomes heartbreaking when they later learn she's paralyzed, possibly for life.
Even after a direct order from Wily during an interrogation, ProtoMan refuses to sell Nomad out and avoids mentioning her.
After ProtoMan's torture, Guts Man, Cut Man, and Magnet Man carry him back to his bed and try to comfort him.
Episode 11's first chapter has Mega Man telling Brain Bot of the good Proto did; he recommends Mega talk to him.
Everyone trying to help Mega out of his depression in the third chapter of Episode 11, and the Robot Master trio trying to comfort ProtoMan.
Mr. Black remembering his wife, Tonya, even if it ends up tragic.
The fifth chapter of episode 11 has Bass saving Roll and resisting the urge to just run off with her because it's not what she would want.
Episode 11, chapter 7 has Roll and Dr. Light reassuring Mega that he's still a hero, and he reflects on those who he's helped and believe in him. And then the ensuing battle goes horribly wrong.
Episode 11, chapter 8. ProtoMan finds the strength to redownload his courage and confidence because he knows Nomad needs him.
Episode 11, chapter 9, has Roll literally slapping some sense into Mega. Then he reviews the footage and memories of all of Wily's prior attacks so he has a clearer mindset of what he's fighting against... and the humans he's fighting for.
Episode 11, chapter 10, has Roll explaining to Boo why she fights, and he understands.
ProtoMan admitting he loves Nomad, calming her destructive programming and lessening her pain.
Episode 11, chapter 11, is full of this in the endgame.
First, there's Mega's concern for his family, the police, and others, letting them get to safety if things become too dangerous.
Then there's Mr. Black electing to not kill Bomb Man, as his true target was Wily, even though Bomb Man caused Tonya's death.
Finally, there's the big moment. ProtoMan is forced to kill Mega Man via the Mad Grinder, and seems helpless to do so due to Wily's override command. But memories of his brother, Nomad, and Mega Man never doubting that he loves ProtoMan convince him to turn his back on Wily, saving his brother's life and the world.
Episode 11, chapter 12, has everyone from the Bonnes, the President, Governor Deacon, the New York police, and Kalinka Cossack reacting to the news of Mega's condition.
It also has ProtoMan literally giving Mega Man his heart to help save him.
Roll has her first talk with ProtoMan as siblings.
When Peekaboo comes in to see Roll, he recognizes ProtoMan and gives him a big hug. ProtoMan carries his warmly and with care. This makes Roll realize ProtoMan means it about leaving Wily.
The chapter ends with happy tears, as Mega Man wakes up, remembers his family, and gives ProtoMan a real, brotherly hug.
The epilogue to episode 11 has Peekaboo giving Mega Man a balloon to cheer him up, Mega calling Kalinka to tell her that he's alright, ProtoMan having a real talk with Dr. Light, Dr. Wily finally regretting some of the things he's done even if it doesn't last, and the chapter ends with ProtoMan and Nomad sharing a happy moment together.
In the interlude to Episode 12, chapter 1, there's the entire Thanksgiving scene where everyone declares thanks for tons of things...and especially for ProtoMan.
The interlude to Episode 12, part 2, has the Christmas scenes. There's Peekaboo's gift from Roll, Mega and Kalinka's scene, and ProtoMan and Nomad's first kiss.
Episode 12, chapter 4 has a brief scene where Mega Man admires a photograph of Kalinka and remembers good times they shared.