Personality
Professor Grisenko acted like a grandfather to Clara during their brief time together and was protective of her, as shown when he shot at Skaldak when he grabbed her head. Clara stated that Grisenko was funny, because he was somewhat eccentric and liked to sing in dangerous situations. When told about the possibilities of time travel his first question was to ask if his favourite band would split up in the future. He enjoyed Western pop music which he listened to on a Walkman, including Ultravox and Duran Duran.
Grisenko was griefstriken and horrified when he, the Doctor and Clara found two mutilated bodies and called Skaldak a monster. He tried to comfort Clara about this later. (TV: Cold War)