1. she is the school nurse or some other figure responsible for the students’ health 2. she is injured or ill, and came to the infirmary for help 3. she is not actually ill, but is in the infirmary for some other reason School nurse is the most obvious one, since it has been foreshadowed in the kiss zombie arc. However, I struggle to think of a quirk for her. Perhaps she leads a very unhealthy lifestyle despite advocating for a healthy one, but that sounds too similar to Momoha. Perhaps it’s a fellow student who’s tired of the actual nurse not being around, and decided to stand-in for her? Having an injured or sick student as the new girlfriend could serve as a small twist given the expectations for a school nurse girlfriend. The range of available quirks is wider too. It could be anything, so given how popular Umamusume is currently, I’m going to take a wild guess and say it’s a girl who enjoys running while wearing horse-based accessories, but fractured her leg doing so. For the last option, for the new girlfriend to visit the infirmary despite not being sick, an easy reason / quirk is that the girlfriend is a hypochondriac.