A sexual fetish involving a previously non-slutty girl losing her sexual morality. Differs from Bimbofication in that, while a sluttified girl loses her sexual inhibitions, she does not lose her overall intelligence.
The act of turning someone or yourself into a sissy, often via sissy hypno, a chastity cage, and wearing feminine clothing.
Being a sissy isn't the same as being a trans woman, as sissification is done as a fetish, and isn't the same as transitioning, though trans sissies do exist.
Sissification is mostly done in femdom relationships and is often combined with other things like cuckolding
Person: How's the sissification going?
Sissy: Great! I feel just like a woman already.