Post Malone Shows Off His Very Detailed Lil Peep Tattoo

Post Malone got some new ink last week to honor his late friend, Lil Peep, and flaunted it -- in all its amazing detail -- as he left Poppy in WeHo.

We got Post Monday night and, as soon as we offered condolences ... he stopped to pay tribute. He flashed the new tattoo of Peep's face on his left arm.

Post also had some kind words about Peep's brief career and his impact on music.

As we first reported, Peep's apparent OD death is now the subject of a police investigation.