Obata said that he drew the SPK "without thinking too much" when the group first appeared in Chapter 60. Obata heard that Mello sent a spy, so he tried to make a character look "suspicious looking." Obata said that he had to "work hard" on all of the characters since he did not know which ones would survive. Obata said that he believes that his drawing skills relating to "foreign characters" are poor; he says that he imagines the characters being "from so far away" and that he forgets how to draw them.