Deborah ga Rival

Asayo starts university and lives alone for the first time. However, the handsome blonde guy living next door turns out to be an okama! Umenosuke Ichimatsu of the famous tea ceremony family is a cool guy who goes by the name of "Deborah." But unfortunately, he's a girl on the inside. So Asayo hangs out with him as a girlfriend… and falls in love with him?

(Source: ComiXology)