>>149039642it's called aohge hair you ignorant 10 years old
https://animanga.fandom.com/wiki/Ahoge
Ahoge (アホ毛, アホげ), literally "foolish hair," is a visual cue common to Japanese anime and manga. Consisting of a single cute, often long, lock of hair sticking out from the top of the head, it is most often used to identify foolish, bumbling or carefree characters.