to cross the line is to dispel the illusion.
the illusion is not disgraceful. the illusion is comfort. it is control. it is a little garden where the seeds of friendship grow into whatever fruits you desire, and you can eat those fruits yourself for the rest of time. to cross the line is to ask someone else how those fruits taste.
tomoyo lived in the illusion long enough to forget. over time, her movements became natural, her motions honed by muscle memory to stop just short of the line. the line, and the illusion, became invisible, until one day, she saw sakura's face faintly glimmering on the other side.
miach didn't know of the existence of the illusion. fediel's advances are uncomfortable when miach lacks a sense of self, so it's easy to push her away. fediel always charges back, so it's easy to push her away. but when fediel stays too far away to push, miach realizes that all these actions were based on illusion.
kiwi was freed by the illusion. when she knows she could never reach the line, she can attack as hard as she wants. she can make the illusion bigger and grander, until she can't see the edge anymore. but when she sees utena within her space, she no longer knows what is illusion.
are you only doing this... because you promised?