Patterns of Yuri at the Girls' School

Hikari loves her classmate Maho, who she's known since they were little. They display their affection for each other so much it draws the suspicions of everyone. But, this is all a show as Maho is actually involved with another girl... After school, classmate Ai asks Hikari, "Is it really okay if your girlfriend is flirting with another girl?" Without knowing what Ai's game is, Hikari finds herself being kissed by her... and seduced. Ai does things to her that she's always wanted to do with Maho. Despite the heartbreak, she's physically enraptured... A feeling of loss quickly takes a turn in this tale of schoolgirl discovery.

(Source: Renta!)