Our body is constantly making serous fluid, which is a clear, yellow, odourless fluid. Similar to engine lube, this fluid allows our muscles to glide over one another without getting stuck. Following surgery, there is the potential for that serous fluid to accumulate in the surgical wound. If there is an excess of this fluid that is called a seroma.Following drain removal, it takes about 48-72 hours for the wound to typically seal over. During that period, a scant amount of serous drainage can be normal. If the site is taking longer to close, or if the fluid is excessive (soaking your sheets) then the most likely reason is that you have a seroma. Fluid likes to escape using the path of least resistance - sometimes that is a weak spot in an incision, but if there is a hole from a drain that is the easiest path. You should meet with your surgeon to be assessed and see if the fluid is accumulating. If so, it may need to be drained or aspirated (sucked out using a syringe). Good luck.
It is typical for things to be clean and dry and healing well after the drains are removed. It sounds like you have a seroma, or a collection of fluid under your skin. See your surgeon as soon as possible.
This sounds like residual fluid that needs to be drained either percutaneously in the clinic or operatively.