I would like to say for anybody who cannot get the MC to defecate: don't just press down C, PRESS AND HOLD DOWN C. If that doesn't work, then it may be a bug.
To the developer: It wouldn't hurt to include instructions to press and hold down C and not just press C somewhere in the instructions / controls / help to make sure people don't think their game is broken (like I did for a little while). Otherwise, love the game (especially how customizable and changeable it is) and looking forward to future updates!