Seishun Otome Banchou!

Hirata Mihane has a scary face and isn't ladylike at all. In fact, she lets her temper get the better of her and often lets out small bursts of violent behaviour—even though she doesn't mean to. Because of this, the entire school calls her a "Satsujinki" (murderous monster). Even so, she's in love with the kind and popular Touma-kun, who doesn't mind the way she looks and is always nice to her. But... will Touma ever see her as a love interest?

(Source: Dazzling Scans)