OMG OMG!!!!! ok, calm down. haha....
i saw this and i freaked!!!
so a poster at seulkifan forum said that before Seulki debuted she was w/ SM and she would've known yunho back then. also, she's a fan of his. supposedly she posted a pic of him in her cyworld:

her old cyworld (supposedly she wrote "this is my husband" under yunho's pic)
but of course (knowing how fans reaction etc.) she quickly took it down. but i think the cyworld still has records of past entries as indicated below:

the red words is just Yunho's name in Chinese (does anybody know what else it says?)
btw, i'm NOT here to create rumor or stir things up but i was just a bit confused...cuz some ppl's replies were like *if she really did put that up and said 'this is my husband'* she would've been totally dissed by dbsk fans...etc. and another person said "i want kim jongmin better" (rofl....dood the guy has a girlfriend, i didn't have the heart to reply to that comment) and another comment was like "well we already know that, the past is the past"
i'm still not sure. haha...god i hope dbsk fans don't come after me either.

[Update]
(man, that forum is gonna make me go crazy...i think they're as crazy as i am! haha jk!)

it's too blurry to see anything but some were going nuts like how it looks like they're kissing (b/c i got the hq version....i was like errr..."calm down guys")