Anzu Yokoyama

Anzu's a lithe and athletic young woman of average height, with both brown medium-length hair and pale skin. She is described as thuggish looking. She is commonly seen wearing the standard school uniform without a tie, with an open collar and no undershirt.

The early story line of the series proves Anzu's easy to manipulate. Anzu is a cheerful and confident person, who regularly speaks to the boys comfortably when many other girls shy away. Despite her somewhat rough attitude, she's genuinely kind and friendly. She is also slightly immodest, showing her cleavage to the boys while sitting with Shingo in the canteen a few times. In the Sports Festival, she reveals her extensive knowledge on the USC. She is shown to be a highly competitive person with high-caliber gaming skill and athleticism, competing for USC jockey for the All-Student-Council Cavalry Battle.

(Source: Prison School Wiki)