Boojoint is synonymous to the words "boo" and "booski". He or she is not quite your boyfriend because you are not claiming one another or not ready to claim each other as "boyfriend" or "girlfriend" but you care for each other in a romantic fashion.
If you make out and have dates, you can still be "boojoint" and not "boy/girlfriend".
Dude: Hey Man, is that your brother's boofont hairdo way back there rockin' out on stage??
Man: Yeah dude, anyone could see THAT. It looks like a helmet.