Sailor Moon X One Punch Man Serena Tsukino does 100 pushups, 100 sit-ups, 100 squats, and a 10km run every day for 3 years when she discovers that she is Sailor Moon at age 11. 3 years later, she became too strong... Note that this story follows the events of Sailor Moon, with a few OPM things referenced here and there. A few characters will be out of character here, and both stories aren't mine, of course.
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