Strickland: [to Elisa] What'd you say to me?
Elisa: [Signing] F - U - C - K
Strickland: What is she saying?
Elisa: Y - O - U
Zelda: Uh, I, I didn't catch it.
Strickland: [pointing at Elisa] what is SHE saying?
Zelda: She is saying "Thank you".
Giles: If I told you about her, what would I say? That they lived happily ever after? I believe they did. That they were in love? That they remained in love? I'm sure that's true. When I think of her - of Elisa - the only thing that comes to mind is a poem, whispered by someone in love, hundreds of years ago: "Unable to perceive the shape of You, I find You all around me. Your presence fills my eyes with Your love, It humbles my heart, For You are everywhere."
Answer: There are a lot of Hellboy fans who speculate this is an origin story of Abe, or at the very least the Asset is the same species, but del Torro has denied it. Abe is a copyrighted character that del Torro's Hellboy was based on, and he doesn't own the copyright. In addition, prior to The Shape of Water, del Torro was in talks with Universal about remaking "The Creature from the Black Lagoon", only making the movie center on the creature's (Gill-Man) perspective and getting together with Kay (the female lead). Del Torro has stated that the Amphibious Man is based on Gill-Man and this film is what he had pitched to Universal, but was turned down by them. Although, a creature developing a love interest in a human female isn't unique, nor is capturing a creature to study (both happen to Gill-Man, Abe, and Amphibious Man). But the fact that Doug Jones plays both Abe and the Amphibious Man only seems to strengthen theories of some connection to Hellboy, but at this point we only have del Torro's word that it's not and why he choose the creature to be so similar at this point would only be a guess.
Bishop73