2nd puberty and maturation

Up to the age of 18 everyone matures exactly as in our world. Once the age of 18 is reached is when we start to see differences with second puberty generally taking place between the ages of 18 and 21. Most people are finished maturing by 20 and it's only incredibly rare outside cases that aren't fully mature by 21. Most of the urges that require indulging fortunately do not oresent earliest in the process meaning most people reach that level of maturity outside of a school setting with children around. At the same time schools which teach students up to 18 will have a private space for those students where the sex limitations are relaxed (seperate to the one provided for teachers and staff although intermingling is not a taboo).

Men: Gradual penis growth, this doesn't happen overnight but during second puberty men's cocks will grow, lengthening and thickening from the average sizes seen in our world to the giant sizes expected here. Ball swelling, again gradually, mens balls will swell as sperm production increases as their semen develops into the nutritious mix that women require. Senstivity to self-pleasuirng acts will similarly descrease. Men who have no yet fully matured can still jerk themselves off but it will likely take more time and effort. Until eventually they become insestive to their own touch, same as how you can't tickle yourself. At some point in this process men will noticed the Switch has occured. It will now be painful to go for too long without sex with blue balls developing. This will progress over time, younger men are able to go for a couple weeks before it becomes unbearable, with the interval decreasing with maturation. Younger men can often be taken by surprise though, suddenly developing pain and feeling the need to fuck quickly. These sudden onsets do not tend to be fatal but it is recommended they be indulged all the same. There is no obvious external cue that a male has matured however an increased production of phermones that comes with maturity means that adult women are drawn primarily to matured men.

Women: From 18 women begin to develop the need for semen as sustinance, with a decreasing requirement for normal food the further 2nd puberty progresses. This will initially present as a hunger or craving for semen that a virign female may not understand if poorly taught. At a variable point in their development women will go into heat. This is considered the true transition to full maturity. Cum lust will present at high levels and then only increase until 2nd puberty finishes. Women in heat will find regular clothes suffocating and transition from dressing like a child to an adult. This change in attire marks to men women who are of age. Women who are of age can dress like they are not if for some reason they want to know they will not be bothered by men, this is very uncomfortable them though so a pretty dire reason is needed. If younger women dress like they are in heat while not and a man sleeps with them this is considered to have been entrapment by the woman and the man is absolved of any wrong doing. Otherwise A man who sleeps with a non-mature women (>18 but not in heat), legally requires clear consent. Consent cannot be given by or for minors.