DC Comics has ordered a New York gallery to remove pictures which show Batman and Robin kissing and embracing.
The Batman character was revived in recent hit movie Batman Begins
The Kathleen Cullen Fine Arts gallery was told it would face legal action unless it removed watercolours of the superhero by artist Mark Chamberlain.
"DC Comics wants me to hand over all unsold work," said Ms Cullen.
Arts website Artnet was also told to remove the series of semi-naked images of Batman and Robin from its website. DC Comics was unavailable to comment.
The colour pictures, which depict the superheroes in a number of homoerotic poses, were put on display in the gallery in February.
Seven images from the collection were subsequently displayed on the Artnet site.
Artist Chamberlain's works have been exhibited in numerous Manhattan galleries since 1991, with collections entitled Neo-Erotic and Gender Tennis among others.
Two years ago an artwork featuring Kylie Minogue's bottom was pulled from the Royal Academy's summer show after the singer's lawyers complained.