The image of the man who thinks by applying a hand to the chin.
It may also be used for the scene to chew a nail and to chagrined.
アゴに手を当てて考える男性をイメージ。
爪を噛んで悔しがるシーンにも使えるかもしれません。
The left hand is a setting that the hand is put in a pocket, and it is slightly sank!
左手はポケットに手を入れているという設定なので、若干めり込んでます!