Diana is the Roman goddess of hunting and the literal equivalent of the Greek goddess Artemis. She also represents wildlife and the woodlands, as well as being the symbol of female fertility. Her appearance in Devil Summoner: Soul Hackers may be a reference to the Diana of Ephesus.
Diana was implemented in October 2015 as part of The Die is Cast questline. She can be fused in a double fusion of Artemis and Hecate.
Shin Megami Tensei: Strange Journey
"A mother goddess in Roman lore, she is the goddess of hunting and the equivalent of Greece's Artemis. Diana is often pictured with a deer at her side and is also known as the goddess of fertility. She is an eternal virgin and has her followers take a vow of virginity. Later Christian influence led her to be named the Queen of Witches."
—Shin Megami Tensei: Strange Journey Compendium
Shin Megami Tensei IV Apocalypse
Diana can teach Nanashi the Madness Needle, Blast Arrow and Grand Tack skills through her Demon Whisper. She benefits from learning Gun and healing skills.
Devil Summoner: Soul Hackers
"A moon goddess in Roman lore, she is the goddess of hunting and the equivalent of Greece's Artemis. Diana is often pictured with a deer at her side and is also known as the goddess of fertility. She is an eternal virgin and has her followers take a vow of virginity. Later Christian influence led her to be named the Queen of Witches."
—Devil Summoner: Soul Hackers 3DS Compendium
Persona -trinity soul-
Diana is the Persona of Megumi Kayano that awakened during a car crash in her youth. While she was able to use Diana to save her parents, she was unable to save her little brother, leading to a complex regarding personas in general. Her fears over summoning Diana, however, are resolved when it becomes apparent the only way to save her friend, Yumi Tasaka is to summon Diana.
Diana is seen using a bow and arrow during the final confrontation with Ayane Komatsubara's clone.