Bauhütte is a Japanese manufacturer of gaming furniture and they make some pretty extravagant stuff, including a gaming bed! At some point, I forget when, they also branched out into “ninja” onesies for gaming. In addition to the ninja zip collar, I also like the “Drop Seat System 6.0” which lets you go to the toilet without taking off the onesie! Unfortunately for me, it has buttons in a few places, which my koumpounophobia certainly doesn’t agree with, and so it’s a no go for me. However, if you are a normal person, the onesie can be bought here with international shipping.
