Dude just fucked her without a condom and then went and put on knight armor when told that wasn’t cool and to go get a condom. Why does he even have knight armor? I’m not sure I’d call that a random break up. Especially if he has a history of trying to avoid using protection.
If you have knight armor and are high as fuck this is the expected result.
Also I think its stolen from DBZA, basically Bulma asks if Vegeta was wearing protection and he notes he is wearing his armor, and thus Trunks was conceived.