The Quaint Snow Maiden is also called the angel of the Quaint Snowfield because it was a monster that healed those that are injured. It can only heal you if you manage to survive and be lucky enough to encounter it. The fact that Adrian could summon such an elusive being is a great testament to how good his karma is.
Soul Recall might summon a random monster, NPC or aspect but it has a hidden mechanism that bases the summon on the summoner's karma. The Quaint Snow Maiden that Adrian has summoned is one of the dead Quaint Snow Maidens that answered his call to help them traverse the Anomaly Dungeon.
It is indeed a great blessing to summon such a magnificent and beautiful being. The Quaint Snow Maiden is also something that the Mokesi Tribe worships as they are also close to that of an Ice Elemental. Their wonderful voice is also said to be the most enchanting thing to be ever heard in the frigid north.