Thanks for query,
This is very common problem due to misuse of computer or videos.people go for porno and sex pictures.
Due to sex stimulation during night they have sexy dreams and in the unconscious mind
they get night discharge.
Do hard work ans physical activity during day time.
Avoid seeing porno,sex videos etc.
Wear loose clothes during sleep.
Have reading of good book,magazine and listen light music before going to bed.
ok and bye.