Monster

[Sexbad]

Maybe they are, on the most basic level as with most insects, but they aren't sentient like dogs or monkeys.

I think sentience is awareness of the world around you. That may be somewhat true since a fly dodges your swatting, but they don't seem to really actually be aware of anything before your flyswatter coming down on them other than what they can eat. The same would probably go for spiders too. They basically do what instinct tells them to do. No relationships other than for the sake of procreation (lucky bastards), no reason to live other than to survive, and nothing to learn and grow into other than what their physiology has predetermined.