‘He had the most peculiarly-shaped head’

Waiting for a tube train yesterday, a big man sat next to me on the platform seats.
He carried large overstuffed cross-body man-bag and was sharing his views with a friend about Arsenal’s performance against arch rivals Chelsea the previous evening.
Arsenal centre-back David Luiz had been sent off and a 10-man Arsenal looked set to lose.
But in the closing moments Héctor Bellerín pulled the scoreline back to 2-2.
This does, however, mean that David Luiz faces suspension, and the man next to me speculated out loud whether Arsenal would buy a player to cover his 3-match absence.
Then the train arrived and we boarded. Only then did I notice that the Big Gooner (as I had mentally titled him) had the most peculiarly shaped head.
It was a triangle with a substantial double chin at the bottom. His eyes were slitty, his mouth a gash; small ears and an all-over inflated, blubbery look.
Above is the first rough sketch I made. It needs work to capture the full essence of this character.
I might lower the eyes and widen the chin to give that odd head the pointiness it deserves.