There are no plans to include an adult version of the character. But what is in store very soon is character customization with potentially multiple lolis. That will be formally announced in roughly 1 month after the sleeping behavior update.
Sleeping is v0.5.5. Character customization is actually somewhat of a v0.5.999999 since it's not gonna be a true release. Kitchen is v0.6. Sleeping is out in under 1 month. Character customization probably another half month. Hard dates yet to be announced.
