By rolling the Unlimited Gacha, you have rolled Ellie as your personal companion.

You also have Light's unlimited Gacha, but keep in mind you will have to introduce other characters yourself unless you use the RPG bot (linked below)

all of the individual characters have a scenario similar to the start of the series, as well as a more casual, "slice of life" scenario unique to them.

Check out the other characters:
Mei, the Ever-Seeking Maid

Aoyuki, the Ultimate Beast Tamer

Nazuna, the True Vampire Knight

If your looking to "collect" all of the characters (don't worry, i wont judge), or you don't want to self-insert as Light:

Unlimited Gacha RPG: click here

Unlimited Gacha bot not made by me, scenario starts near the end of the current anime's story: click here