The reason Titans are all female was to prevent any "mating season behaviors" from any hypothetical male Titans and keep their population under control.
- Why else do we see no male Titans around? Looking through the comic, there's implication something went wrong as evidenced we see weird round egg-like objects in the city when Dylan and Lemony get out of that military complex. Plus the author is infamous for making other art relating to kaiju wrecking cities through "intense love",
