En cours de chargement...
Lily is experiencing the expansion caused by a fertility enhancer. The only upside of her drastic feminization is that the professor on whom she has a crush on starts paying extra attention to her, and he begins to reciprocate her feelings in the process. The nearly immobilizing changes are supposed to be completely reversible. As long as she does not get pregnant, that is. An hourglass expansion story.
The heroine does not want her feminine parts to grow, but she can't do anything to prevent it.