Senku Ishigami is the main protagonist of DR STONE and is friends with Taiju Oku, a strong but not so smart childhood best friend, and Yuzuriha Ogawa, taiju's crush and skilled seamstress. Senku is known for his bluntness and dark humor. he is highly logical and doesn't outwardly show his emotional side. His catchphrases consist of "Ten Billion Percent" and "Get excited."