Say I Love You 5 by Kanae Hazuki
Friendship? Forget it! Mei Tachibana has no friends - and she doesn't need them! Ever since her friends' betrayed her in primary school, she's sworn off friendship entirely. All it leads to is betrayal and heartbreak, and she can cope just fine by herself. However, one day everything changes when she accidentally roundhouse kicks the most popular boy in school! But Yamato Kurosawa isn't angry in the slightest - in fact, he thinks his ordinary life could use an unusual girl like Mei!'