Pankocchi, there's no male equivalent to menstruation but this is the best way I can explain the feeling of morning wood to you. Contrary to popular belief the morning erection isn't due to erotic dreams, but merely a consequence of neurological activity in the brain during sleep. While morning wood is also associated with youth, meaning boys on the cusp of puberty and teenagers as far as I'm concerned it's just a natural part of waking up. In any case, this is how a boy feels when he starts getting proper erections:
https://www.youtube.com/watch?v=i2Nr2xbuXHcThis is how it feels as a mature adult:
https://www.youtube.com/watch?v=zA0U84BhrroThis has been your daily penis update, hopefully we can discuss penises in the future as well, because penises are beautiful.