You mean like in real life when you hear a bell ringing instantly when the girl gets fertilized by your creampie?!
Just kidding, but I have to say it is a nice subtle implementation of pregnancy mechanic. Someone likes to cum on her face, okay, someone is more a creampie dude, fine too, but don't cry if your little, forgetful D gets impregnated ^^ I mean, the mechanic would be even better if it expands to other males. You avoid cumming inside her, but others will cum inside her (by your wish, by accident or maybe she wants it), which then also can lead to possible pregnancy. Same for condoms. But maybe this is all way too much, DmD isn't a pregancy simulator ^^