I'm too lazy to correct an old comment but no. mitsuki doesn't and will not turn into a child or disappear, everytime they have sex.
the immortal jellyfish (T. dohrnii) doesn't revert back to it's polyp state as soon as it reaches sexual maturity. IF the Medusa is under a stressful environment or damaged etc, it reabsorbs its tentacles and reverts into a baby cyst and starts it's life cycle again, sooo they can live forever atleast theoretically according to research.
I'm too lazy to correct an old comment but no. mitsuki doesn't and will not turn into a child or disappear, everytime they have sex.
the immortal jellyfish (T. dohrnii) doesn't revert back to it's polyp state as soon as it reaches sexual maturity. IF the Medusa is under a stressful environment or damaged etc, it reabsorbs its tentacles and reverts into a baby cyst and starts it's life cycle again, sooo they can live forever atleast theoretically according to research.