I'll take this one as the resident homosexual moderator.
They're called no-show loafer socks.

They work like a charm and produce this result when worn with fancy shoes:

This is also what high-class, country club, preppy guys use in order to appear extra stylish.
Here's a quick bonus tip for those that really want to impress the "ladies"... After a good shower, where you scrub your feet well with soap, make sure to properly dry your feet (get in between the toes), clip your toenails, don't be afraid to add a thin film of moisturizer to your feet and then once your feet are sufficiently dry, generously apply a deodorant/antiperspirant throughout the soles of your feet and right underneath your toes. Afterwards, apply the no-show socks, followed by your loafers, hit the town with your lady friend and when it comes time for sex and you remove those shoes+socks, she will be amazed by how well groomed your toes are, how soft your feet feel and how good your shoes/socks/feet smell.
You're welcome.
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