Falling Demon Rain

A true sorcerer is born with magical powers. The sorcerer is not born with a full set of usable magical powers. New magical powers are learned, as the sorcerer exercises the magical powers that he is born with. The main problem is that the exercise of a sorcerer’s power involves dealing with demons and certain other things, in the magical worlds.
The careful sorcerer learns the expansion of his powers, a bit at a time. Each gain of powers typically involves the risk of the sorcerer’s life. A sorcerer uses magical powers to run what might be called a business. A sorcerer deals with demons who actually live in the magical worlds. The life (sometimes lives) of a demon, is a hard life. A demon can obtain things of value, from the magical worlds. In the process of obtaining things, the demon is sometimes injured. An injured demon will then respond to a call by a sorcerer. A sorcerer can, perhaps, heal a demon or even improve the power of a demon. Unfortunately, a demon can obtain a great deal of power, by killing a sorcerer and absorbing at least some of the powers of the sorcerer.
A sorcerer can summon a demon, or demons, (although the summoning of multiple demons is very dangerous.) A demon may bring something of value to a summoning, hoping to swap the item of value for needed healing, or whatever. A demon may come to a summoning, hoping to kill a sorcerer to gain needed healing, or whatever.
A demon is a higher dimensional being. A demon may be able to access things stored in very secure three dimensional storage, such as a safe or locked room. The safe or locked room is only really secure in three dimensions, in higher dimensions there may be easy access.
(One other thing that a demon can do is to kill living three dimensional beings. Such demon killings can be ordered by a sorcerer, without any obvious connection to the sorcerer. Such a killing seems to be just a random attack by a very powerful, mysterious being. The careful sorcerer arranges to be somewhere, where the sorcerer could not have done the murder. An enemy can be eliminated and the sorcerer has an airtight alibi.)
As in the three dimensional world, magical world information is rarely free, The best information that I can obtain, as I travel, is that Uncle Allos apparently dealt with a very powerful demon, from way up in the multidimensional magical worlds.
(I am a young, mostly untrained sorcerer, I could not live with Uncle Allos, as two sorcerers can not live in close contact.)
I could not live with Uncle Allos, but he gave me something of very great value, at a very great price. I am nearly seven feet tall and very muscular. Uncle Allos unlocked the path to physical superiority for me. However, to gain physical superiority, I had to walk the path. To really walk the path, I had to work out very hard, on a day by day basis. I did the work and, as a result, I am very strong, very quick and I have enormous reach.
Since Uncle Allos is dead, I can live in his house and even use some of the things that Uncle Allos learned and entered into his grimoire.