I Love You Twoson

Listen up, buttercup. This joke is playing on the words "two-son" and "Twoson." Onett and Threed are video game locations from Earthbound. Twoson is another location from the same game and is used here as a pun that sounds like "two-son". It's like saying "I love you too, son," but with video game flair. You probably don't know Earthbound, which says a lot about your gaming taste.