To see someone or something without him/her seeing you.
I'm afraid to go too deep into the ocean--who knows what creatures are pulling a giant squid on me. It's been said that we haven't seen them, but they've definitely seen us.
1. the act by which a monstrously large and rather unfortunately nude person wearing a pointed dunce hat and a flag football belt continuously puts ink (of which the individual has an ample stipend) in his/her mouth and, with the consent of another decidedly kinky party, proceeds to spit the aforementioned ink onto the similarly naked body of the willing partner as a prerequisite to further imminent and equally debauched sexual depravity.
2. the massively colossal and scandalously bare individual who is executing the act known as the Giant Squid.
Peter: I got a Giant Squid from Sarah last night. Ink is a bitch to get off.
Harry: Yeah, I can see that fat bitch being a Giant Squid. You know, in spite of the insane amount of body hair on her.