What makes you so sure?

At first he was "No I'm not a femboy, I do not want to be femine"
Fast forward to today and he constantly crossdresses, wants to be feminine, shaves all of his body hair. Some of the stuff may be just AGP symptoms, but to me the pipeline reminds me of myself.

>>45118128
You're projecting, like all trannies do with guys like this.

so how could I tell if it is not just projecting?

>>45118175
This is a very sensitive subject and should be treated with great care. If he's not trans and you ask him if he is, he might see you as a groomer and your relationship will be soured. Even if he is there's a chance he'll rep harder out of shame. You can always throw him something vague like "you know you can always talk to me about what's on your mind and I won't judge you, right?" but even thats kind of manipulative. These things need to come about naturally. Just be supportive. Maybe show a bit of your gynephilic side (that is if you're gynephilic and not gonna break up with him if he troons) but really you just have to wait and see.

Tell him you think he's a tranny.
You think that will go poorly?
But if it's so obvious if you say, "You're a tranny," they should react at least downplayingly.
Or they'll go, "Bwah? Wtf? No? What?" And you can move on with your lives.

>>45118003
if you top him, ask him if he'd ever consider getting SRS for you.
if you don't or you're sure he's not bottom dysphoric, ask him if he'd have preferred being born as a girl, if he could keep his dick.
ask him what he likes or doesn't like about being a guy.
ask him what he'd change about his life if he was certain he'd only have another 5 to 10 years to to live.

poland mentioned