The first one, and the most formed idea, is a supernatural style thing. It starts off ordinary enough with a guy leasing a new apartment, but he soon discovers that the place kinda smells. To combat the smell, he sprays some odour elimination stuff around the apartment and opens the windows to airate it, then he leaves to go do other things whilst it's sorting itself out. Later that day, he comes back with a bunch of stuff for dinner to find a woman asleep on the floor, basking in the light of the window. Considering that his door was locked, there were no signs of forced entry and his apartment is on the third floor, he starts to wonder just how someone got in (not to mention why they just fell asleep).
He takes measures to arm himself in case the woman is just a really bad burglar, then wakes her up and demands to know her intentions. She merely rubs her eyes and says that it seemed like a nice place to take a nap. When he asks her how she got in, she says that she climbed through the window, pointing at the large open window before them both, but when he looks outside, he can't see any drainpipes she could have shimmied up, just plain wall. He seems a little uneasy and when he asks who she is, she tells him that she's a cat. He thinks it's a joke and finds her somewhat pitiable (she was rather easy on the eyes as well) so he decides to at least feed her before sending her on her way telling her that she can't just go sleeping in peoples apartments. He probably thinks that she's used this place as a place to sleep before and just didn't realise it was taken now.
The first act of the story will be him getting to know her through their various encounters and him wondering whether she's just delusional (and just really athletic) or actually a cat. There will be subtle hints, some of which the main guy probably isn't aware of which point towards the girl either being followed by some kind of organisation that sounds sorta government-y or criminal-y. After some time, he'll get dragged into a world of well-concealed monsters, just living every day lives amongst humans. I don't know what would happen beyond that point though.
The second idea is much less fleshed out. It was just called 'Colour' and takes place in a world completely devoid of colour. The main character, a girl, soon finds that she somehow has the ability to manifest colour and that with each colour, she gains different abilites or can manipulate different things.
It would look way prettier if it was a visual media though.