Justin Bieber, we need to talk about your naked-guitar-grandma serenade.

Dear Justin Bieber,

By now we're fully aware of the fact that your bulging biceps, impeccable pecs, and six-pack-everything can't be contained by clothes. Shirts are for wimps. And speaking of things we know about you, we realize that you're super-close with your grandparents. All (mostly) good stuff! But what we're trying (and failing) to wrap our minds around today -- after seeing some NSFW photos of you serenading your grandma in the nude -- is... WHY ON EARTH WOULD YOU SERENADE YOUR GRANDMA IN THE NUDE?

Yeah, we know, technically these recently surfaced photos are almost a year old (TMZ reports that Justin surprised his grandma in the buff in October 2012, aka Canadian Thanksgiving). And technically this came BEFORE the mop bucket peeing incident slash the balcony-loogie incident. And yes, we know you hid your most important parts with an acoustic guitar and this was only meant to be a joke -- but Justin, Justin, Justin... Call us conventional, but nudity and grandmas generally don't mix.

Now, don't get me wrong -- we're more than happy to stare at any pop star's well-toned butt. Especially when it comes with a guitar and a song. But... just... know your audience, Justin! Your maybe-maybe-not ex Selena Gomez might've been down for a guitar-and-butt serenade. On, say, Valentine's Day. But not grandmas and Thanksgiving! Just something to think about the next time you feel like stripping down. Also, can't believe I'm saying this, but(t)... I never thought I miss your droopy drawers.

Your Friend,

Rachel

Photo credit: Getty Images