Hakui no Tora wa Gokudou de Zetsurin: Yami Isha Yakuza ni Maiban Dekiai sarete

Overview

Momo was a track runner on her way to the world championship until an injury she sustained ended her career. She's been told by doctor after doctor that she'll never be able to run competitively again... that is, until she meets Dr. Dan Sendou, who says he can get her back to her former condition. His confident words move Momo's heart, and she trusts him. But, Dan is actually a young mafia lieutenant who treats gang members! When Momo finds out his secret, Dan shows his true colors and tells her he needs to sleep with a woman after treating someone... Momo thought this would just be a one-time thing... but now he's filling her up in bed every night...! (Source: MangaPlaza)

Source: AniList