Sex/Semen retention after NoFap

The aim of NoFap isn't to abstain in the long term from sex and ejaculation. Some even go back to masturbation after their reboot, but that's completely up to you.

As far as semen retention, it isn't something that's really part of NoFap at all, that's an entirely separate belief that the retention of semen helps you which there isn't really much scientific evidence of aside from the fact that ejaculations can affect testosterone which goes back to normal at around a week.

It all depends on your personal beliefs, but technically speaking yes it's okay to ejaculate and have sex after NoFap. NoFap is really just about rebooting so you're able to do those things normally like you should've been able to all along.