Manthika

Isekai'd into an otome where the original script is Law and nothing you can do changes anything?  Good thing you don't have a Bad End worse than expulsion.  The FL goes on after expulsion to live a 'Slow Life' and is soon followed by the ML who likes her and secretly moonlights as a fluffy animal as well as a neighboring country's prince.  Who pulls strings for her in the background because he likes her.  Amazing. 

This is pretty much your average otome 'villainess' isekai, but it's not bad as long as you don't mind cliches up the wazooski.  And a somewhat bland plot.  And an awkward romance- but it's not that bad.