Milli Yorks

First appearing in Rance II, she is Mill Yorks' older sister. Milli appears as both a tough warrior and glamourous girl in daily life. But she also can be quite affectionate at times, especially when it comes to her sister, Mill, even to the extent that she dares to enter a dangerous labyrinth just for her. She has a massive appetite for sex and, needless to say, gets along with Rance well because of it. She lives primarily as an adventurer and warrior but somehow also runs a pharmacy with her sister.

Rance 2
Milli goes to the labyrinth to save her sister, Mill, who is currently possessed by one of the rings' power. Unfortunately, her party was exterminated by Green Hannies and that left her as the only survivor of the group. Rance saved her just as she was about to be killed. With her purpose still yet to be fulfilled, Milli joins Rance's group mainly because she believed hers and Rance's motives are about the same.

With her phantom beasts, Mill is literally untouchable. According to a certain mummy, a special sword is needed to slice through them. The sword itself is protected by a Golden Hanny, and is very strong. After defeating the Golden Hanny, Milli obtained the special sword (which apparently may only be held by females). With the sword equipped, she can slice through Mill's phantom beasts to ensure the party's win. Mill, who cannot accept her defeat, still tries to resist Rance, who doesn't want to extend the fight any longer. Rance suddenly threatens Milli with his sword, using her as a hostage to soften Mill and force her to just give up peacefully so he can just do his "job". Eventually, his plan succeeds, and Mill is free from the ring's possession. But it turns out that Mill was just a little girl all along, and not a beautiful woman; the ring caused her body to change. Rance is floored.

Mill and Milli run a pharmacy in Custom, and the people seem to already forgive Mill since they have accepted her as one of them.

In the last chapter of story, Milli partakes in battle against Ragithis who just regained the ring's full powers, though beaten and is forced to retreat along with the rest of group.

Rance 3
Milli fought as part of Custom Defense Force against the invasion from Helman. With Rance on Custom's side, they fought together against enemy that had the advantage in strength, and still won in the end. After that battle, she fought again with the Helman army as the Liberation Army of Leazas.

Although she did help to defend Custom and free Leazas, she also made a lot of mistakes during several battles, in which Rance is very concerned with. Mill said that her sister's condition is just not at its best recently.

She took medicines made by priestess Cell. As for what her disease is, it never really stated.

Kichikuou Rance
She joins along with Mill, Shizuka, Maria, and Ran after Rance conquer Custom.

Rance Quest
Spoilers ahead.

She is already dead by the time of the events of Rance Quest. When Mill Yorks joins Rance's party, Milli's photo can be seen equipped on her which she keeps as a memorial. It mentions her age at the time of demise as 23 years.