High lust on your side and a lust increase can cause it. It's not a 100% thing.how? it says my room is close so i don't get an erection
If you are not happy with that, you can use the cheat from my last post in the console.
Just changing your lust to 100 using the console won't work to give you an erection, since you just change the value directly and all the other code which is used to trigger the erection is not processed.