Does anyone know if in order to enjoy "You Suck" if you have to read the first  book "Blood Sucking Fiends" first?

It was a long time ago that I read "You Suck", but I had not read "Blood Sucking Fiends" prior to it and I enjoyed it all the same. I caught on to everything pretty easily.

I read them in order (Bloodsucking Fiends first, then You Suck) and enjoyed Bloodsucking Fiends better.  But you can probably understand them just as well as standalones or out of order.

Reading them out of order won't make much difference to your overall story enjoyment, but there are things that will make a little more sense if you read BSF first. Blood Sucking Fiends was definitely the better of the two.