Dragon stance: Dragonborn
Affiliations: Listener of the Dark Brotherhood, Guild Member of the Thieves Guild, High-ranking Companion, Student of the Mage's College.
Main house: Proudspire Manor in Solitude.
Preferred Follower: Vorstag
Family: Vorstag (husband), Marcus (accidental husband), Tanwen (mother-in-law), Sanguine (father-in-law), Lucia (sponsored child, partially canon)
Mentionable Friends: Erdi, Erik the Slayer, Adrianne, Ulfberth, Balimund, Ysolda, Ria...
Past/Current relationships: Vorstag, Marcus, Ulfric,
Enemies: Taarie, Delphine (frenemies?),
Race: Dunmer (Dark elf)
Dragon stance: Pre-Alduin
Affiliations: Speaker for the Dark Brotherhood (previously Listener before Kira), Guild Master of the Thieves Guild, Student of the Mage's College.
Main House: Honeyside in Riften.
Preferred Follower: None, seeing as she is a stealth character.
Family: Sanguine (husband), Marcus (son), Kira (daughter-in-law)
Mentionable Friends: Balimund, Karliah, Mjoll the Lioness, Hafjorg, Ingun Black-Briar, Madesi, Wylandriah
Past/Current Relationships: Sanguine, and maybe an unknown lover from Morrowind. She has knowingly friendzoned Balimund.
Enemies: Commander Maro, Mercer Frey, the Thalmor, Maven Black-Briar (frenemies)
Race: Altmer (High Elf)
Dragon stance: Studied the Voice
Affiliations: Arch-Mage of the Mage's College, possibly going to become an assassin for the Dark Brotherhood.
Main House: Vlindrel Hall in Markarth
Preferred Follower: Argis the Bulwark
Family: Argis?, Nelacar (partner),
Mentionable Friends: Argis, Nelacar, Faralda, Onmund, Savos Aren, Brelnya
Past/Current Relationships: Nelacar
Enemies: Ancano, Taarie, Ondolemar (frenemies?), Elenwen,
How they're connected: Tanwen and Kira, of course, know each other directly through both the Dark Brotherhood and the Thieves Guild. Kira met her first through the Guild, and then found out a little while later that Tanwen was also in the Brotherhood. Tanwen had a surprise child with the Daedric Prince Sanguine, and they married. Their child, Marcus, sort of chose Kira as his wife (unbeknownst to her). Kira knows Adelmar through her lawlfully wedded husband, Vorstag. Vorstag and Argis are friends, or even relatives (at least that's my headcanon - why else would they be warriors in Markarth with the same warpaint?) and Adelmar prefers to have Argis with him always. Also, both Tanwen and Kira joined the Mage's college (for their own reasons - neither of them are particularly magically oriented) and Adelmar is the Arch Mage after Savos Aren.
He doesn't have a save file, nor am I sure I want to make one for him. He is the son of Tanwen and the Daedric Lord Sanguine. That makes him the son of a master thief and assassin, and the Prince of Debauchery himself. He's a spoiled prince with unlimited power and resources. He could topple an empire if he truly wanted to. But what he decides to do is follow Kira around and annoy her. But not even in a constant annoyance, following her around everywhere, even to the bathroom. He pops in every so often, at the most inopportune times, and then only speaks to her in the daedric language condescendingly. He does, however, protect her if needed, and when she uses the Sanguine Rose, he is the Dremora that is summoned. Kira and Marcus are also married. Somehow.