He (34M) claims I'm (25F) his girlfriend but hasn't directly asked me. Advice?

Are you asking for a definition of the word "boyfriend"? I am not really sure what you are asking.

You are in a sexually exclusive relationship (i.e. have an agreement to not be with other people) that has lasted for months. I would definitely not call that "casual". I would call that being your boyfriend.

It sounds like you are avoiding something. Are you?

I would be hurt if the woman I have been dating for 6 months used the word casual. You might want to think about your feelings for him... and if this is an important relationship to you, I would suggest an apology.

He needs to know that he is important to you. If not, you may lose this relationship. You are telling him that your relationship doesn't mean anything to you.

I believe you’re the one overthinking it in this case.

I’m 61 and female. I’ve had 2 marriages, plus s 1 long term (6 years) relationship, and I guess maybe a couple other men I was serious enough with to differentiate them from casual dating.

Not one of them ever asked me to be their girlfriend , and I never asked them to be my boyfriend.
Actually, the subject of exclusivity never came up with any of them. That’s because it was apparent we were either in each other’s company, at our jobs or school, or in some way engaged in life where being on a date with someone else wasn’t likely. I can see where that subject could be a good thing to discuss with many couples. However, I frankly never had the energy or excess time to pursue dating even one other man when I was with someone I cared about, plus everything else that life entails.

In short, he considers you his girlfriend. Simple as that. It sounds as if he has other important things going on and you being his girlfriend is one less thing he has to worry over. It sounds like it’s a comfort to him that in his busy life you are someone he can count on. You’re a positive for him.

The question is he a comfort and a positive in your life? Is he someone you can rely on and trust? Are you happy about having him in your life? If you answer yes to these, feel free to call him your boyfriend. After 6 month of a good relationship with each other, I think that’s a given.

To an extent, I admire your asking yourself if this person is at this level in your life. It seems way to many people both male & female refer to someone as bf/gf after 3 or 4 days, or because they know each other on IG.

He did ask if you were seeing other people and wanted to make sure you were not... to me that means you are exclusive and are a couple. As you get older beyond the teen and early twenties most people do not ask are we boyfriend and girlfriend.... after months of being together and being exclusive it should be apparent that you are an exclusive couple and thus girlfriend boyfriend.

Now if you are questioning getting even more serious like engaged or if there is potential to marry ... I’d give him slack until he is done with his exams...

I’d approach that and discuss once he can mentally be in that space as well.

That’s an excellent point linkat. A 34 year old man isn’t going to ask someone to be their gf.

If you don't want him then tell him so