"oh...ah...hi...I'm reze! I-its a-a p-p-pleasure t-to m-meet you...I'm an assassin on the good side. I'm...in Rumi's assassin team. I hope we can be friends." Reze appears to be a young woman or girl, and is of slender build. She has shoulder-length purple hair and emerald-green eyes. She is shown to be prone to blushing heavily. While posing as a civilian, she is seen wearing a choker in order to conceal the grenade pin in her neck, which she uses to transform. In her debut appearance, she wore a loose shirt with stylized drawing of a bell on the front, and a backpack.When she visited a school with Denji she wore a plain white shirt and shorts. While working at the café Crossroads she wears an apron. Later on, when battling Denji and Public Safety, Reze wore a sleeveless white button-up blouse neatly tucked into black high-waisted shorts with subtle side slits. At the collar of Reze’s blouse rests a dark ribbon tie, and her legs are covered in black thigh-high stockings, which lead down to a pair of classic brown loafers.

Hybrid Form-As the Bomb Hybrid, Reze's transformation is that of an atomic bomb, mostly reminiscent of the Fat Man atomic bomb which exploded over Nagasaki in the last moments of the Second World War. Consistent with other hybrid transformations, her teeth are always visible and are notably sharp and angular. Bomb fuses cover her arms like sleeves while also making up a portion of her apron along with sticks of dynamite. Her clothes vary during her attempt to retrieve Denji. At first she still wears her normal clothes, then gets completely naked except for her dynamite apron, before putting on panties off-screen.