So is this a forced sissification/TF?
Geared towards to female or male protag?
It's not forced per-say on a whole. There's some storylines / characters that do force TF and transexual transformations. But you can (with a fair amount of effort) avoid female TFs. There is also at least 1 event and one magic item that you can get to transform to be more masculine.
A lot of it is focused on having the PC shift towards female, mostly by having more feminine actions lead to body TFs and sometimes mental effects too, but masculine actions shift you the other way. Like doing yoga vs strength training at the gym. Much of the random content is pretty balanced between the male, female, and transexual PC, but most of the character arcs are more with the PC either becoming or already feminine. There's some male focused stuff, but not terribly much.
You can also be gay, straight, or bisexual in any form in the game.