I'm afraid I can't really point you towards any specific make or brand other than to say I have a number of them and are pretty much what I wear to bed. They are fairly comfortable, although not really all that short...about mid thigh length and are very similar to boxers in design only looser and without the front flap. I will alternate between that and a sleep shirt during the warm weather and during the one or two colder months in our state I generally wear a full leg version of sleep pants and a t-shirt or full sleeve two piece PJs. All I can recommend is to look around on the internet for something that looks like what your seeking, although the aforementioned sleep shirt beats any pants hands down as it allows you to totally freeball underneath. I got mine on ebay and it looks similar to this (not me...pic of some other dude):
Although I realize some men might think they are too similar to what women wear, but I love it, even if the drawback is when my wife wears her nightshirt it can sometimes result in my exposed junk inadvertently rubbing against her bare ass and interrupting my sleep

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