I will point out since certain people have ignored the fact he stated plainly that he's in a multiplayer game..
So yes you can change your main char, click the button just above the rest icon, it should look like a computer I think, it's the one that brings up the screen with all the char's show, where you can assign who in your multi player game who has control of what chars..
just take the tick off your main char then click him name and delete I think is the one to press, make sure he dones not have any plot items on him as they will all be destroyed (possibly making the game unwinnable)
You'll now have a blank slot to put a main char into, I'd suggest using shadowkeeper to set his XP to the same as the party and alter any bhaalspawn ablitys that should not be there, or should be there as the case my be.
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-Jenn
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