Daru is obviously overweight, something few characters have taken notice of during the course of the story and later becoming a significant plot point. Daru always wears a dark green/olive t-shirt and a pair of blue jeans along with his signature yellow cap and sandals on his fet. In one of the anime episodes, Daru is seen wearing a yellow Hawaiian shirt.
Daru is obsessed and extremely talented with programs and computers, capable of hacking into the mainframes of top-secret organizations and processing complex computer codes. He is very proficient with the IBN 5100, though is unable to make out any of the information he dug up due to his lack of skill in English.
Daru, like Okabe, enjoys making Future Gadgets, but is not as enthusiastic and has voiced his desire to sell them for money briefly in the visual novel. Daru is apparently bad when it comes to naming, as he would always add an irrelevant model serial and version number to the end of the gadget's name. He has a habit of finding something perverted on what the others are saying, much to the chagrin of Kurisu Makise.
Despite his perverted tendencies and obsessions with anime and gadgets, Daru is easily one of the more down-to-earth members of the lab, rivalled only by Kurisu. It's usually up to him to be Okabe's voice of reason when his 'mad scientist' antics get out of control, such as when he tried to calm him down when he was shocked to see Kurisu alive and well.
He supposedly has an obsession with both 2D and 3D girls and is a big fan of Faris. Daru supposedly possesses rich knowledge when it comes to dating, as he gave Okabe "advices" on his upcoming date with Ruka, though Okabe claimed that Daru was just using experience from his H-games, and does not have any real "skills".