Rein started to get fragmented information about how his symbol worked and in about a week, he was able to understand his ability a little bit. The information that he got was not really detailed. So even after learning about his symbol, Rein did not become an expert at using this symbol of his.
So his ability from this symbol could be represented with three pairs of concepts. They were hot and cold, fire and ice, then finally cheerful and depressed. So basically it was the combination of three pairs of opposite words.
As for how Rein was able to use this, for the first pair of concepts, he was able to increase or decrease the temperature of anything that he touched. And for the second pair of concepts, Rein was able to create fire or ice out of thin air. The concepts were not this simple though as Rein was not sure if he could make someone cheerful or depressed. He would need to test that in other living beings and Rein did not have the permission to do that for the time being.