Goner Clam Girl, also known as Clam Goner, is a Waterfall NPC exclusive to the Nintendo Switch version of Undertale, where Clam Girl gets some new dialogue in the epilogue of the True Pacifist Route. At the final line of her dialogue, Clam Girl turns into Goner Clam Girl.

Description: Description: Hello. He-he-he-he-have some respect and don't spoil the game. It's impossible to have mysteries nowadays, because of nosy people like you. Please keep all of this between us. If you post it online, I won't make any more secrets. No one will be impressed. It will be your faaaaault. He-he-he-he-ha-he-he-ha-he-he. If you are seeing this, I believe this is some sort of error message or something... Heh, if you can see this... ∂̷σ̸η̸т̷'̶ ̵¢̸σ̴м̶є̵ ̴в̵α̸¢̸к̷.̷.̴.̸ ̵¥̷ð̶µ̵ ̵Ð̶ï̵r̶†̴¥̶ ̵h̴å̴¢̸k̸ê̵r̸