I don 't think they have any bias towards people who want them to be their best friend. They just do their bidding and live off their care while they are waiting for the right moment to betray them.

我认为，对于那些想与它们成为好朋友的人，它们是没有偏见的，它们惟命是听、靠主人的照顾过日子，同时却又等待时机背叛他们。