It is best to take a shower after sex so that you can wash off the lubes and cum and anything else you have used.
If you don’t it could start smelling fishy and things could happen. Sometimes you can end up having bacteria growing in which it can give off the fishy smell.
Sometimes you will even get sweaty if you go long periods of time.
There is also other things that can happen also. You can track the sperm everywhere that you do not want it. Lubes can get everywhere and sometimes it can stain things.
It’s just best if you shower and wash your toys to prevent anything that’s harmful. It’s just a good idea to do this.