Rather than doing a Bronx accent (which many people do when voicing Sans), I decided to go for a voice that could sound tired and lazy, while also working as a more serious voice in heavy situations. When I look at Sans' design in Undertale: his constant grin, his eyes being his only way of expressing how he feels, and his overall relaxed mood and stance, I see him having this voice. I also think the voice works for when he tells puns too, because it makes him seem like a chilled-out comedian (which he essentially is).