For her to wear thongs.....me to wear thongs!!
Depends on what kind of evening you're planning. If it's going to be an evening of slow, erotic buildup which culminates in a lot of sexual activity, then by all means, panties are superfluous. Knowing a woman's sexual gate is open, so to speak, is very arousing. But it's also fun when she's wearing panties, so when the time comes, it's like unwrapping a present.
Panties for definite! Full cut maxi briefs, midi briefs, tangas or mini briefs in cotton or cotton / lycra (e.g Sloggi) colours preferred but black or white is nice too; simple, quality, classic, timless designs! Not into lacy, silky, ott frilly stuff.
Prefer panties....
as for what style... heck.. too many to narrow it down.. but if I had to pick one right this second.. a nice white lace thong in the style of the VS "Lacie"...
Or maybe a tiny T-back that just barely covers...
thongs..they are sexy on women
Anything feminine or nothing. It's a thrill finding out.
No granny panties though please!