<human>: Not sure if this belongs here or in another subreddit.  Sorry if I should post this somewhere else.  

The other day I was texting my friend's (we'll call her Tiffany 20 yr old) boyfriend (we'll call him Mike 23 yr old).  I've known Tiffany for about 5-6 years and Mike for the last two.  We we're talking about a random girl I used to date and I mentioned that she had a great ass.  He replies "like this" and sends me a pic of my friend Tiffany's ass.  

Before I could reply he immediately tries to cover his own ass saying "that's a girl i used to get with years ago" and then changes the subject to how I should get a case for my new iphone.  I let him slide at the time and continued on talking about the iphone case.  

I know for a fact that this is Tiff's ass because she has a tatoo that is clearly visible in the pic he sent.  The thing is I'm not sure she knows it was taken.  She's not the type of girl (at least I think) that would let him take pics like this and if you look at the picture she seems to be asleep and he pulled the covers back.  Even if she is letting him take these pics I doubt she wants them shared.

My issue is this.  Mike is a self centered borderline alcoholic douche bag.  He treats Tiffany as if she's his slave most of the time and she's more of a motherly figure than a girlfriend at times.  Tiffany knows myself as well as other friends and family don't like Mike much and she admits that he is an asshole from time to time.  I want to bring it up to her, but I feel like a SAP saying "uhh hey is this your ass?"  Also, since it's obvious I don't like Mike, I don't want it to be "you're just trying to split us up" sorta thing in her mind.  *Note I'm married so there shouldn't be any of this I want her all to myself sorta stuff.*

What would you do in my situation?

Give me a shortened version of the text
<bot>: Got sent a pic of my friend's ass from her boyfriend everyone dislikes.  Not sure she knows it was taken (could have been sleeping).  Should I bring it up to her and if so how?