First main I ever had was a really bad Sonic OC on a Sonic forum that was also a trash fire ultimately. If we're excluding OCs...I think it was Nick from L4D2. That was just privately between a friend I had at the time and very self indulgent.

First DWRP journal though? Amy Rose from STC. I played her over at the Wake.

In terms of current mains, we have Ash Fox on the OC front and Walter Sullivan on the not-OC front