To reproduce: As soon as possible after being transformed into a girl (mostly), go to your room, undress for some private times and play with your boobs. Do this enough time for two (or maybe three?) size increases.
Go to the cafeteria, enter the break room. Try to switch clothes. The protagonist can't get into the uniform. Try to go outside. You can't leave, you can't start your shift, you can't talk to anyone; you are softlocked.
By the way, I enjoyed the game, though it was a bit too much clicking on repetitive sections for my taste. For example, after you have played for a week, I think it would make sense to have a "Go to work" button from your house (or room). I realize this would wreck some other events, so this would need to check if there are any events on the way to work and play those out first. Probably too much work for now, but perhaps a suggestion you can implement later.