Texas Smash! (Patreon)

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After the villains escaped, Inko's body wouldn't return to normal. All Might asked Medicine Girl for help. Short of capturing the villains responsible and getting information out of them, her only suggestion was that Inko would have to lose the weight by herself. However, because of Inko's state, exercise was obviously impossible, so the nurse had to come up with an idea... That same day Inko was rolled into a spacey room, alone with All Might. He explained the unorthodox method Medicine Girl had proposed, and asked for her consent. The plan was simple: They would fuck until the calories generated by the enemy quirk were burnt off and her body returned to normal.

While that confused and embarrassed Inko greatly, especially since her body was like an over-bloated beach ball, she also felt an inner burning that pleaded her to accept, so she did. All Might grabbed her, lifted her like a huge yoga ball and penetrated her with his all mighty rod, which would have never fit her regular body in a first place.

Minutes of rigorous rutting passed, but All Might realized his strength wasn't failing him as usual. Something about this woman gave him an extra vigor he hadn't had for so long. Inko also felt a pleasure like she never had before. After half a hour, All Might felt he was reaching his climax, so he told her to get ready. And so he said his usual motto: "Go beyond: Plus Ultra!" And released his load into her. 

Unfortunately, it did little to help her burn calories, in fact, her body bloated bigger than ever. All Might apologized profusely, though Inko didn't seemed to mind. Despite her being stuck and swollen even more, she didn't regret the experience, and even asked if he would be willing to try again sometime soon...

This is gonna require a lot explaining to young Midoriya, though.