Ah, Officer Orcot ... what am I going to do about you? I do enjoy your company. One of these days, I may not let you leave.

Count D & Leon Orcot

Detective Leon Orcot meets Count D after the death of actor Robin Hendrix - having learned that a common link in a number of recent unexplained bizarre deaths is that all of the victims were customers of the pet shop, Leon suspects D of having sold Robin a venomous lizard. D welcomes Leon in to the shop and serves him tea - as well as an explanation to Robin's death, though Leon refuses to accept it. Throughout the series, Leon visits the shop, tries to prove D is engaged in illegal activities, and claims that he is interested in shutting down the pet shop and arresting Count D. D, in turn, tends to treat Leon like a beloved pet, one that often misguided, perhaps not as intelligent or mature as others, one that is amusing and dear, but still a pet.

However, there are indications, often strong indications, that feelings of a different nature exist on both sides. D's attitude with Leon is often flirtatious, and throughout the series he attempts to help Leon when the detective reaches a low point - look at the stories with Gattolotto or the butterfly story. Leon, for his part, seems jealous when D seems to date Wong (T-chan in his human form) and goes on his date with Monica in vol. 9. For all that Leon claims not to trust D, if he didn't why does he leave his kid brother in D's care, letting Chris live at the pet shop? In turn, if D didn't care about Leon, why does he take Chris in?

Finally, the ending of the manga run, where D saves Leon's life, and Leon leaves his life behind to go find Count D and return to him the picture Chris drew of them at the pet shop, disappearing entirely leaves little question for me that the nature of their feelings for one another go beyond friendship. Your opinion may differ, but this is what I see.