Not from charging. Weird Lock screen appeared out of nowhere. What is it?

[Daniela Mew]

I was not charging my phone or anything.

I was only watching a youtube video. All of a sudden, my phone went black and this new lock screen popped up. There seems to be settings on the upper left corner, but it only says "turn off" and when I select that option, it almost sounds like a threat.
It says "Oops, really? One more chance, Please. If closed, Lock Screen won't bring any convenience to you." And the options are "YES. PRETTY SURE." or "NO. MAYBE LATER."

It says the time, date, battery life, and sometimes a Yahoo ad pops up as well.

I have no idea what it is and I've searched and have not found any information on it.

 

[chanchan05]

It's a lockscreen ad from one of your installer apps. Probably it updated in the background as you were watching video. Just select yes pretty sure.

 

[Daniela Mew]

Thank you very much. I appreciate the help.