Of course! Wait... noo!!! But well... yes...
Actually, it depends.
I don't like it if characters just don't use a condom. I rather prefer if they forgo the condom for some reasonable reason.
So it depends on the scene and the characters.
Humans do dumb things when they are drunk, in love, horny and so on.
What should the condoms protect against? Only pregnancy? STDs? Both?
Does the girl trust the guy? Does she trust him to pull out to avoid pregnancy? Does she think she can't catch an STD because he's a shy guy (maybe a virgin) who hasn't much experience who even asked for a condom?
Does the guy dislike condoms? Does he care if the girl would get pregnant? Does the idea even turn him on? Does he care about STDs? Or does he even think that the risk is only minor as a guy (as he doesn't get the cum inside)?
Does he start with a condom and pull off or does the condom break (no idea how that can happen, but heard of it...)? Does he ask her to cum in her mouth because he doesn't want to cum inside the condom? Does he compare the orgasm with the condom with the creampies he had with his former girlfriend? Are they like crazy when they search for a condom or when they pull it over his cock?
So... I prefer it when no condoms are used, as long as it is reasonable and fits the characters and the situation.
Depending on the scene it can add some additional spice (especially thoughts of why they do it like they do)
If there are no reasons, go for the condom, cum inside, knot it and throw it into the trash (or whatever the characters would most likely do with it).
You're characters know how they would do it, so you can always "ask" them
