Akira-kun Kamoshirenaishi Akira-chan Kamoshirenai

Kazuma, obsessed with the thought of "Since you're in college, it's time to fall in love for real!" meets a girl as beautiful as an angel. After getting nursed back to health by her after being beaten up, Kazuma searches for the angel to thank her. After searching campus high and low, he finds someone who fits the description and it's a m-man...?! No, a woman?! No, which is it?!

(Source: Shogakukan, translated)