Series: Mitsudomoe
Also called: Micchan, Choujo ("oldest daughter")
One of the three main characters, the Marui triplets. Mitsuba is the oldest by a matter of minutes; you'd think that wouldn't mean much, but it's gone straight to her head. She's haughty, sadistic, and nasty, a tsundere with almost no dere. She has the requisite twintails and is only interested in the opposite sex when there's netorare potential.
Judging by image count, Mitsuba is the most popular of the triplets for fanart.