While Ash’s Pikachu adores ketchup, Detective Pikachu loves coffee. In a recent interview, the game’s creators explained why.
Famitsu asked why Detective Pikachu has an old man voice, and producer Hiroyuki Jinnai explained that Ikue Otani’s cute Pikachu voice work is exceedingly well-known.
“That’s why, as this is an adventure game, we wanted to bring out the type of mood in a hard-boiled detective story.”
That, however, doesn’t explain the coffee.
Following up on what Jinnai said, director Naoki Miyashita added, “If you’re talking about a sleuth, then typically you imagine there is a pipe as part of the standard character toolkit, but as one would expect, in its place we dialed that down to coffee. However, it [coffee] is slightly grown-up and brings out a certain coolness.”
So while classic detectives might smoke a pipe, that is probably a bit much for Detective Pikachu, hence the coffee.