Most Helpful Girl
Not in itself, but it can be suspicious. Why be on a dating site or app when you're in a relationship? Maybe it's for an ego boost and validation from other people, or maybe you're using it to keep your options open or hook up behind your partner's back. Doesn't sound good, especially if you're hiding it.
Maybe if you trust each other enough, and you both know it's just for fun and not hooking up (or you're in an open relationship and that's okay), it's not a big deal, though. Each couple has to decide for themselves where the line is and what they're comfortable with.0