Help! 2 cats with bathroom problems

Hi everyone,

let me introduce my cats, pera and hermes. I got them together from a local no kill shelter when they were 7 weeks old, yet they are unrelated. they are also of different sex, pera is a girl and hermes is a boy. They both are shorthair stray cats. 

Now they are around 5 months old, really cute and really playful. However, we've been experiencing occasional bathroom problems. until few weeks ago, it was just hermes, peeing around basically. They are not allowed in the bedrooms anymore, because hermes likes to pee on beds, and neither me nor my roommate are fond of cat pee in bed. I guess it is about territory, yet I don't understand why, they did grow up together, and they like each other a lot, there shouldn't be any competition between them.

A couple weeks ago, I found poop on the bathroom mat. I thought it was because the litter box was full ( I keep the litter box in the bathroom). I usually scoop it everyday, but that weekend I was sick and I stayed at my boyfriend's apartment-and my roommate didn't scoop it in the meantime. I cleaned the litter box, changed the litter, and thought the problem was solved. Two days ago, I realized the bathroom mat was peed on-well, i used some nature's miracle and washed it.

Today, however, a strange thing had happened. I was in the dining room, doing some work, and I saw Pera scratching the wood floors. I called her, she looked at me, went to the bottom shelf of the bookcase and started to scratch there. After she saw me watching her, she went to the bathroom, stood right in front of the litter box and took her pooping pose basically. It was me who held her and put into the box(I'm glad I was there on time). She continued there, and she didn't hide it after she was done. It is also really strange because she is always so clean(even obsessive compulsive about cleaning herself and hiding her poop). I'm not sure if she's sick or is it purely behavioral-I will take her to the vet tomorrow morning, but she looks playful and happy.

Also, I know multiple cat households need multiple litter boxes, but my apartment is really small and I have no space to put an extra litter box-until I move out in june.

Please help, what can I do?

Thanks so much!

First of all, thank you for your concern!

They both were neutered by the shelter when I got them, so there shouldn't be a problem about it. The box is a covered box-yet they've been using it since they came to my house basically. Let's see what the vet will say, I will try taking off the cover afterwards.

Well, there is a pantry- but honestly it is the last choice-food&litter box doesn't strike me as a good combination. Also, no matter how much I scoop (at least once a day)-and I use the crystal litters-there is always some odor, I came to learn that it is inevitable. I will try cat attract litter though!

well, yes, we went to the vet, and as i thought, both pera and hermes are pretty healthy. I took the door of the litter box yesterday (I attached it only few days ago) and it seemed to help (knock on the wood).