What type of rear does that muscleskins have? Is that the athletic, lean or half? I didn't know about that brand and I think i'm going to have to get one now for lapswimming and it will replace the seobean where my ass bulges out of the rear. ;)

My muscleskins back is the "lean" one. Very cheeky. I think I would not wear it at public pool.
The front is VERY low, and you have to manscape of course...
I will order one between Athletic and Lean (you can custom it between options) with a drawstring and a 1 inch side for lap swimming. I like my briefs being a bit cheeky.

Bulge speedo
 

Wore this to swim laps today. Realised it’s a bit more “bulgy” .

Your suit
 

How much back coverage does it have?

Back
 

I’d say 3/4th ? Slightly less than traditional Speedo.

To paraphrase Doc Brown in "Back to the Future"

"Back? Where we are going we don't need no BACK"

Fun red and white thong.

do you wear that to swim laps in as well?!?!?

When I am alone yes. But I prefer a thong to swim, or completely naked if I can. Last summer I often swam naked in the sea at a nudist beach. Love the feeling...

looks like you swim laps for fitness or at one point you were a professional swimmer. The pictures of you pulling the rio back into a thong are is something i've done in the past and wish I could swim laps daily in a pool in a thong!

Wearing a true thong in a swim pool would be a wonderful feeling. You said when you are alone you swim in a thong or naked if you can. Have you ever swam laps in a pool in a true thong or naked?