a predicament

so i was laying in bed dreaming about this really big spider in our house, when i heard the door slam and frazier started barking. back story... Chris keeps waking up really hot in the night so he goes into the living room and sleeps on the couch with the front door open. i have "encouraged" him not to do this in the past because bugs come in the house. i can't confirm this is what he did last night (because it's 5:30 am and he won't wake up to answer my investigatory questions), but i think it is. so... i woke up to a loud bang, got out of bed to see what in the heck is happening and then i hear this little sound under the couch. what!? it's like a thumping or chewing or something. it moved from one side of the couch to the other and it stops whenever i move stuff around. so i'm almost certain that there is a creature living in our house now and i'm so very unsettled about this. i don't want to go back to bed because i feel like i need to babysit this creature in case he decides to relocate to another part of the house. what to do... what to do...