Yes. When You have around 75 socialize point thingies with a girl/boy you will have the option to Propose to them. Click propose and hopefully they will Say yes
get in the shower then pause the game when you're in the shower then clcik SAVE GAME, save the game and then turn your PSP CONSOLE off and your sim should be naked.or get in the shower then you'll be...
I've played this game myself multiple times and even did a little research on the web trying to find out myself if a Sim can marry on Sims 2 PSP, and so far it's been a NO :(