First of all, this guy sounds a bit like a dirtbag to me, and just be wary of him, because he could be using you or something.

Also. In this case the 'K' sounds like, i give up on you (because I assume he is just after one thing)

And the 'ohhhhh' could've been him trying to make you feel guilty/like a partypooper for not doing what he wants.

My advice, would be to steer clear of him, untill he is mature enough to handle a real relationship

Well obviously, he doesn't care about you, just sex. He's probably talking to three other girls trying to get the same thing. You said no both times, which means you deserve better than that. My advice is to move on

It means he really doesn't care what you have to say...he sounds like a douche for wanting a dirty picture btw

K = Oops, I don't know what else to say, so I'm announcing defeat without showing my embarrassment

Ohhhh = I see, okay, right, ah-huh, I don't believe you (sarcastic)

k is like a short way to say o.k

and Ohhhh, means oh i get it, or oh, i did not know that

p.s don't send him dirty pictures, he might post them online.

He just wants something to masterbate to, trust me. He just wants some arm candy. Nothing special. He wants you for your body. But take that for a compliment, you have a nice body..?

It means he acknowledged that you won't send any dirty pictures..

That the conversation is over. Or rarely that he/she is too lazy to write 'OK'. Don't show him your stuff. You'll probably regret it.

that means he doesn't want you to have babies. K in ancient latin literally meant "if you don't abort the baby i will kill you"

k is short for okay so he basiclly just said okay to your answer