Random text conversations you have had

Gf is short for girlfriend. I checked his profile. He is still together with her with her pics so I'm confused and a bit paranoid in why the random text after almost a year of silence.

They're probably half assed feelings then. Feelings he doesn't logically intend to do anything about, but he wants to see where his heart lies through light conversation. Things probably weren't going well between him and his gf. It might not have been a fight, he could just be overall discontent. I'd say if you two had a great friendship before, then maybe it's not the case and he simply misses the fun you two used to have, but generally speaking he wouldn't be having those thoughts if his relationship was going well.

Indoctrination? Does that mean I get to be a doctor?! I'm gonna be making so much money. I need 52 cc's of morphine stat!

Not sure if serious. It means the information your lacking is cause for separating you from the general community you're perceived to be in or around, and educating you on that knowledge would serve as a complete inclusion into that community. In this case, there's a lack of understanding of the "otaku" community by a few members, of which that misunderstanding could serve as a break in communication currently or in the future.

He knows me from a past job we worked in. Different departments. We never hung out and barely talked. Neither one of us knows much about each other. So I doubt any forms of strong g feelings happened. Though you are probably right about him not being completely content with their relationship or he wouldn't do random text to girls saying the whole miss you part.