Otaku Circle no Elf Hime

Otaku Princess: a female member (and usually the only member) of a predominantly male club. For those members who have never experienced contact with a female, they treat her like royalty. Thus the phrase "Otaku Princess" was born.

For the quiet Satou of the Character Research Society, he is familiar with the term but never did he expect a literal princess in the form of the elf princess, Rumiria. Unable to contain his lust for her, he pours those thoughts into erotic drawings he doodles in his sketch book. Then one day Rumiria accidentally opens up one of his sketch books and sees what's inside and Satou finds himself in a situation beyond his greatest fantasies.

(Source: Denpasoft)