Unou Tsushima

Unou shares Sanou's strong belief in the superiority of Abnormals. The brothers regard themselves as comparatively ordinary members of Class 13 without allowing that relative weakness to diminish their confidence around Normals.

He is exceptionally close to his twin. The two frequently speak in sequence, react together and present themselves as a matched pair when explaining the Flask Plan.

Unou's certainty is repeatedly tested as the Student Council survives encounters that he and Sanou assume should stop them.

Unou is an Abnormal, although the manga does not identify a personal named Abnormality for him.

Like Sanou, his established function is guarding the Door of Rejection rather than serving as one of the Flask Plan's principal combatants. He therefore receives little opportunity to demonstrate an independent fighting style.

The twins explicitly occupy a lower level of extraordinary ability than the Thirteen Party, effectively making them the "normal" end of Class 13's Abnormal spectrum.

Unou and Sanou introduce Medaka and Zenkichi to the Door of Rejection when they arrive at the underground Flask Plan facility. The twins explain the obstacle and observe the attempt to pass it.

After Medaka surprises them, they accompany the advancing group and observe its battles with the Thirteen Party. Their commentary supplies an insider's perspective on how extraordinary the Student Council's progress appears to members of Class 13.

They remain closely paired throughout their appearances rather than receiving separate storylines.

Sanou Tsushima is Unou's twin brother and closest companion. Sanou Tsushima and Unou guard the Door of Rejection together and routinely speak as a pair.

Medaka Kurokami surprises Unou by overcoming the Flask Plan's entrance obstacle and continuing into the underground facility.

Zenkichi Hitoyoshi accompanies Medaka when the twins explain the Door of Rejection.

Hakama Shiranui coordinates the Flask Plan to which Unou and Sanou belong.