Sister of the Groom

I went to a lingerie shower and I felt a little odd giving that kind of gift especially since I didn't know what size to get, it's not like buying clothes. So I just gave a gift card to Victoria Secret since she didn't register anywhere

One of my friends got married back in November and she had her SIL as MOH. All her bridesmaids got her just some sexy underwear and bras (one got her lube!), but her SIL got her the most funny and embarrassing things. It was a great time. She got her fuzzy hand cuffs and to be honest I can't quite remember the rest, but all the items made us crack up. I wouldn't think of it as weird, I would just go with the flow or even be funny about it.

I agree with PPs. If you get her something cute like a satin cami and shorts set, that wouldn't be awkward!

It might be a little odd for you but apparently it doesn't bother her. Lingerie isn't just limited something naughty/super sexy. It could be just a slinkly/silky gown trimmed with lace (see below link).

https://www.amazon.com/dp/B01COS3VVK/ref=twister_B013SXXPHK

I agree with above. It doesn't have to legit be lingerie! I told my mom I didn't want lingerie at my bridal shower that I wouldn't want to open it in front of everyone. But my mom said she had mentioned to my sister (MOH) that it's traditional for the MOH to get something like this for the bride. I might just tell her okay fine but give it to me at the bachelorette instead then!

No, I don't think so! Especially if you are close. You can always give her something less "naughty" and do a silk pajama set or bride tank top or robe!

I went to a friend's bach party recently and although it wasn't a lingerie party, I decided to get her customized underwear with "Mrs. _____." They were cute but not overly sexy and it wasn't weird at all. Maybe something like that would feel more comfortable? They were basically shaped like bikini bottoms so not overly revealing.