how do you visit nessa? i dont know where to click to visit the college, the option is removed from kalis door but is there anywhere else? if youve completed the college part do you miss out on nessa? thas unfair, it wizzed by without giving me much chance choice or warning
The option is on Kali's door in the evenings (weekdays iirc), as stated already. She hasn't completed college yet as far as I've played (v0.16). You can't miss out, the game is pretty much designed that way.
Only things to "miss" are major choices made very clear to you, like Slave or Love Route for Nia and Sylvia, which you can just save before that choice, load a save, or load an autosave if you saved over. There's also a cheat for Patrons to reset the route should you wish (before you ask, I'm not a Patron anymore).