Joseph Brook from Gary D. Schmidt's Orbiting Jupiter is a complex character, initially appearing reserved and gruff due to past trauma, but also possessing a soft heart, exceptional intelligence (especially in math), and deep sensitivity. He is fiercely loyal and courageous, driven by his love for Madeleine and his desire to find their daughter, Jupiter. Despite his tough exterior, which includes a history of violence, his capacity for love and the nurturing provided by his foster family, the Hurds, allows his vulnerability and true self to emerge.