love key not working? [spoilers]

[enaboo]

i'm currently in chapter 2 and have bought the love key, though i've waited 2 nights and nothing has happened?
i'm wondering if events have been stopping it, as of the night i bought it, kaito's event happened and the next night was the insect meet and greet.

i know ryoma should be dying the next day - so there will be a trial, which means the key will be put off again. i'm unsure as for what to do, do i just wait it out for a night that there isn't any events? i worry that i wont be capable to using the key on kokichi, given if the trianing with kaito continues - it wont stop until he dies, most likely, meaning kokichi will be dead by then too.

[Lots Of Blue]

Yes, I believe you're right about the key not working on nights with certain events, so you should be good to go if you just wait.
About what you wrote in the spoiler tag:
You don't get to choose who you "use" the key on, the game picks someone for you at random. So my advice would be to not worry about which characters' events you get to see during the main game and just hold off until the postgame, where you'll have plenty of opportunity to see everyone's love key events. (It's a lot easier to earn enough money for the keys at that point too, so that's another benefit)