What is the difference between pansexual and bisexual?

Heteroromantic, bi or pansexual probably.

It might be worth pointing out that the reason for labels like this is to allow people to talk about how they feel, and to make it clear that there’s always other people who feel the same way. It’s not to put people in boxes where they must stay - something that happens far to often.

True.

In the case of the hypothetical which @HeyHomie mentioned: “if a guy only dates women but would bone dudes only casually,” such a term would also let such a man avoid admitting/acknowledging that he is sexually attracted to men, if he feels that being labeled as “gay” or “bisexual” would be socially damaging to him.