- Designated Hero: To some Haru, who threatens Yamaken with breaking his arms and legs if Shizuku chooses him, and later comes very close to pushing him off a patio, threatens to rape Shizuku of all things in one of their earliest interactions to get her to keep quiet, and acts (justifiably) violently numerous times, sometimes with a side effect of accidentally hitting Shizuku out of all possible targets. And he's still being viewed as cute by fans and is criticized In-Universe more for being "too spontaneous" or "irresponsible" rather than for his thuggish behavior.
- Draco in Leather Pants: Yamaken is easily one of the more popular characters in Japan, placing first in at least one popularity poll, even though he is introduced as a bully early on in the story and at first grows to like Shizuku out of spite for Haru. He gets more Character Development as the story continues, but he still remains a jerk throughout the bulk of it.
- Ensemble Dark Horse: Natsume, for being so sweet and awkwardly funny while also greatly desiring her friends' love and attention, and meddling a bit too much in their affairs to get it, though she is well-meaning. She is surprisingly relatable to and popular among many fans.
- Hollywood Homely: Shizuku is stated to be plain and have the fashion sense of a grandma, but she's still rather attractive to Haru and Yamaken.
- Ron the Death Eater: Haru gets plenty of this. Despite being an all-around good person, albeit one whose emotions often get the better of him and with a serious lack of social skills, some choose to see him as a borderline-murderous sociopath for his often questionable behavior, ignoring his moments of genuine kindness to his friends and his compassion for pretty much anyone who needs his help. In fact, most of the violence he commits is actually in the defense of another person.
- Ship-to-Ship Combat: Fans are split between Haru and Yamaken when it comes to whom they wish Shizuku would end up with, usually preferring Shizuku with the character that they like more.
YMMV / My Little Monster