Amazingly Embarrassing Parents: Hyun Soo's parents appear to be decent people: they actually like Hyun Soo and promote his music. However, when they try to have the boys play at their restaurant, their boss is a Upper-Class Twit who doesn't care much for rock music. Hyun Soo overhears and slinks away.
To scare the Strawberry Fields boys, Ji Hyuk throws a guitar pick at their dart board—and it sticks. The next time we see Maro, he's taken up using picks instead of darts.
Ji Hyuk records one of the songs that Seung Hoon wrote, and find out that Su Ah has it on her MP3 player. When she is looking for her MP3 player, he asks, "[Are you looking] because of Seung Hoon's song?" She replies, "[I'm looking] because of your voice!"
Celebrity Paradox: In episode 2, Eye Candy members are shown at a karaoke bar with two of them singing Infinite's "Be Mine." Hyun Soo's actor (Kim Myungsoo/L) is a member of Infinite; he doesn't sing the song but he's watching them with a smile.
Disguised in Drag: Byung Hee runs to school in a dress because he had woken up in Mr. Kim's daughter's room—and was now being chased by Mr. Kim. When we next see Byung Hee, he's in his school uniform. Much later, one of the other male students is seen wearing the dress.
Dragon-in-Chief: Pyo Joo is a really interesting version of a Dragon-in-Chief/Dragon with an Agenda. He exacerbates the rivalry between Eye Candy and Strawberry Fields because of his tendency to make rash decisions. In fact, Seung Hoon spends most of his time taking the blame for Pyo Joo's actions because Eye Candy naturally believes that Seung Hoon is behind all of Pyo Joo's actions.
Funny Background Event: Just as Deo Mi says "I hope [Eye Candy] don't end up in our class," 3 of the Eye Candy boys are shown in the background through the glass windows passing by the room, pausing, and then coming back.
Garfunkel: According to Seung Hoon's sister, everyone in Eye Candy but Ji Hyuk and Hyun Soo can be replaced.
Gentle Giant: Do Il, who is also The Quiet One, commands respect from gangsters and other delinquents as soon as he comes into view.
I Want My Beloved to Be Happy: Do Il's face darkens whenever Woo Kyung chases after Ji Hyuk, but he doesn't protest. When Woo Kyung misses her chance to give Ji Hyuk a Valentine's present, Do Il mentions that she missed her chance "this year too."
Milholland Relationship Moment: After his Secret Stab Wound causes the band to lose, Hyun Soo spends a couple of school days just lying in bed, blaming himself. When his friends come to visit, they all just clamor on top of him, tickle him, and laugh the incident off.
Plot Point: In order to find Seung Hoon a birthday gift, Deo Mi suggests that Su Ah go to "Paradise." The audience doesn't find out what Paradise is until Eye Candy walks into the store a bit later, and Byung Hee bumps into Su Ah there. (Paradise is a music store.)
Punny Name: Eye Candy moves from Dongnae (동네) High to Jeongsang (정상) High. 동네 means "neighborhood;" 정상 means "normal." At one point, Byung Hee says, "there's no hope in this neighborhood" when he's talking about their old school.
Byung Hee always react to serious threats with a simple "Yep" and a smile.
Dongnae gang leader: Do you want to die? Byung Hee: (nods) Yep. (smile)
Pyo Joo: You want me to replace your drumkit and and apologize? Byung Hee: (nods) Yep. (smile) Pyo Joo: Are you serious?
Sadist Teacher: Though his hatred stems from the fact that Byung Hee slept with his daughter, Mr. Kim who follows Eye Candy to Jungsang High is downright antagonistic. He gets better when this role is annexed by the Jeongsang High principal.
Secret Stab Wound: Hyun Soo delivers a guitar performance with a bleeding hand at the HR Rock Festival Byung Hee had signed the band up for—until Ji Hyuk figures it out and forces him to stop by hugging him.
Screw the Rules, I Have Money!: Byung-hee's death is compensated by blood money — not an uncommon concept in South Korea, but still infuriating to the members of Eye Candy.
Speak Ill of the Dead: Eye Candy's rival gang from Dongnae and a majority of the Jungsang students waste no time in insulting and disregarding Byung Hee's death.
Special Guest: When Kim C asks for booze and offers to buy the Eye Candy boys' instruments, they think they're hallucinating.
Spiritual Successor: Shut Up Flower Boy Band picks up Flower Boy Ramyun Shop's timeslot on the same network, tvN. The two shows are marketed as part of the Oh! Boy Project "series," even though there's nothing similar about them, except for the fact that the main cast involve high school students.