Apple ID that's not mine keeps popping up? - 1

I just got a new iPhone 4S, and for some reason the Apple ID that pops up when I need to log in is often "kevin_ukh@126.com". I've had an iPhone in the past as well so I have my own Apple ID that I put in when I was syncing this new iPhone. I have no idea where kevin_ukh@126.com came from. And it sounds like a spam email to me… What should I do? Is there a way for me to get my iPhone to "forget" this email address? Who is kevin_ukh@126.com?

You can try following:

Go to App store > featured and scroll down and there you'll see Apple ID,
tap and sign out and after that sign in with your Apple ID.

Another option is to reset iPhone to factory settings.