The picture you have uploaded is a centipede, there generally harmless to plants and only eat dead leafs and like damp soil. There are many species of centipedes, the one you have just generally likes to borrow down in the soil and likes to hide out in dead wood and damp rotten tree bark. I understand that you don't like them crawling around your house though. I prefer millipedes there one of my favorite's. I'd recommend buying some fresh potting compose. Take your plant outside and take off all the old soil from the roots by using a hose and gently rinse off the soil and clean out the pot then bring it back inside and re-pot your plant using the fresh compost.
