feminization ()
Where a male-bodied character is forcibly changed to become more stereotypically "feminine", in behavior, appearance, or body. Frequently involves gender transformation, but not necessarily - it might just involve an ordinary male character being transformed into a girly one, or there might be no transformation at all and a character could be forced to crossdress. Mind control, brainwashing, and domination are frequently involved.
When a female-bodied character is made even more stereotypically feminine, this is sometimes referred to as bimbofication.