Soak, but don't wash.

I evidently doesn't count as washing it, since I usually chuck it into the sink and fill it up with water too, leaving it there for the rest of the day, until I eventually put it into the dishwasher. It prevents the cereal remnants from crusting up on the bowl. Imagine if your roommates didn't even fill them with water.

Have you ever tried to pry off Cream of Wheat or Mini-wheats after they've been stuck in the bowl for a couple of hours?

It's breakfast. Dishes are meant to be done in the evening.