bearodactyl I'm pretty sure jerking off makes it easier to fall asleep as well (at least for me I found it I close my eyes right after I would be super tired and have no trouble getting to sleep)
Orgasms, at least for males, release a flood of natural melatonin, which you could always try to replicate (or intensify) with melatonin supplements. Melatonin doesn't stay in the body for too long though, so that's why you should close your eyes right after. Melatonin supplements take about 15-20 minutes to kick in, but once they do, if your eyes are closed you'll be out. Don't take more than ~6-8mg a day though.
Melatonin has been shown to intensify testicular cancer in patients under 45. Do not take Melatonin if you have a history of being a weeb. Talk to your doctor and ask if Melatonin is right for you.