[Houshalter]

There are actually a number of parasites that change the behavior of the host. Toxoplasma gondii makes mice try to get eaten by cats.

[kaybe]

High percentages of humans carry that one. It studied once in a while whether it influences human behaviour [0].

I haven't found onen that discusses love of cats as a result, sadly.

[0] last section here: https://en.wikipedia.org/wiki/Toxoplasma_gondii