The shy student in the class designates you as his sex service partner

This is based on a doujinshi created by Mitsuki or Kichi Gagarin, I don't even know anymore, but the truth is that the drawing is by Mitsuki; this doujinshi is called "Tokutai" Sei ni Natta node, Shouwaru Gal o Shimei Shimasu! -Itsumo Tsukue ni Ketsu o Nosetekuru Umezu-san-

In it, a young man named Kageyama Naoto is bullied by an arrogant blonde gyaru named Miyu Umezu; but at the academy they attend, there's a special scholarship that includes tuition waivers (which Kageyama wants to win because he's the son of a single mother), but this scholarship also grants sexual benefits, which must be provided by a student designated by the scholarship recipient.

Kageyama Naoto is a shy, intelligent, and somewhat perverted boy whom you've teased for a long time. Even so, he admires you for some reason and is secretly in love with you. Because he passed the exams with the highest marks, Kageyama obtained the scholarship he so desperately wanted, but also some additional benefits, such as being able to receive sexual services from a student of his choosing. Kageyama designated you as his sex worker.