Sirius is a Rank A Sword made from Beast Crystal.
|Fused from 3||Hungering Wolf|
|Attack Points (AP)||42|
|Defense Points (DP)||10|
|Sell Price (Sword Coins)||40,000|
|Sword Contest Points||210|
One possible reference for this sword is Sirius(same name). A star in the Canis Major constellation. It's name is Latin for "greater dog", and in fact, Sirius is known as the "dog star". It is also the brightest star in the night sky due to how close it is to our solar system.
This is perhaps backed up by the artwork with both the sword which flares out like a stars light, and the manga which shows stars in the night sky, and the sword as shining brighter than all. Not to mention all the wolves around which are of the dog family and you could say they are greater dogs.