- "If you are gone I'll die right away. Take responsibility because you kidnapped me."
- — Beatrice to Kinzo as they leave Rokkenjima
Beatrice "Bice" Castiglioni (ベアトリーチェ "ビーチェ" カスティリオーニ Beatorīche "Bīce" Kasutiriōni ) was Kinzo Ushiromiya's first and only true love and his "mistress", as said in many rumors. Introduced in 1944, Beatrice was the daughter of an Italian Social Republic naval official. Often called Bice (pronounced "Bee-che"), she accompanied her father to Rokkenjima on a submarine containing ten tons of gold, though her father died during the trip. Because Kinzo was the only person able to speak English, he and Beatrice became interpreters between the Japanese and Italian soldiers on the island.
- Requiem of the Golden Witch
- Umineko no Naku Koro ni Chiru (Manga)
- Umineko no Naku Koro ni Chiru: Nocturne of Truth and Illusions
- Kinzo Ushiromiya - lover
- Beatrice Ushiromiya - daughter
- Sayo Yasuda/"Beatrice" - grandchild
- Lion Ushiromiya - grandchild (Miracle fragment only)
Beatrice is of Italian descent. She has ginger-blonde hair and blue eyes. She seems to be of average height, well-endowed and has fair skin. She wears a red fulard and a white shirt, along with green army pants with brown boots.
Beatrice is a light-hearted person who is very intelligent. She comes from a noble Italian family and is treated as a noble lady. Despite her origins, Beatrice is quite a tomboy and a tough woman, and dislikes the treatment she receives for her family name. She is very friendly and tells her friends to call her "Bice."
Beatrice is seen only in a flashback of Kinzo's memory in Requiem of the Golden Witch, when Lion Ushiromiya and Willard H. Wright ask Kinzo to tell them about Beatrice. Kinzo first met Beatrice while he was stationed at Rokkenjima as a soldier during the war. Her submarine was badly damaged and had just barely arrived to Rokkenjima; plenty of men had died inside it due to a gas leak, with Beatrice's father included in the casualties.
As Kinzo spoke English, he and Beatrice acted as interpreters for the two different troops, which allowed them to get close to each other. The two found sympathy for each other and talked about each other's lives and interests. As they talked, both of them understood the beauty of life and fell in love. Later on, tension arose between the Italians and the Japanese soldiers when the Italians unloaded 10 tons of gold. A fight broke out between the two for ownership of the gold, and in the end only Kinzo and Beatrice survived, though with Beatrice hurt badly. Beatrice asked Kinzo to stay with her and "kidnap" her until her death. Kinzo, however, refused to let her die, saying he'll kidnap her forever, and took Beatrice to Niijima via boat to see a doctor.
While on the boat, Kinzo referred to her as a "witch, a golden witch." He entrusted Beatrice to a doctor on Niijima, asking him to keep Beatrice and his visits a secret. The doctor, who ended up being Nanjo, tended to her wounds, and she and Kinzo headed back to the mainland, though she was kept a secret as Kinzo was already married. The two secretly met when they could. Later on, Beatrice died giving birth to her and Kinzo's daughter. Kinzo names their child 'Beatrice' in honor of her late mother, and takes her to Rokkenjima to live in the hidden mansion Kuwadorian.
- Her clothes (from the fulard to the pants) are red, white and green: the Italian flag.
- The nickname "Bice" shares the same nickname with Beatrice Potinari, a person inspired in La Divina Commedia.