Your Intelligence and Charisma scores increase by 2.

You know the Thaumaturgy cantrip and use it excessively, especially when introducing yourself. You can use it without expending an action.

You gain proficiency in the Arcana skill, and if you do not have proficiency in the History skill, you are considered proficient when making a History check related to magic or magical items.

When an effect forces you to make a saving throw to avoid being frightened, charmed, or stunned, you can choose to replace the ability modifier for the saving throw with either your Intelligence or Charisma modifier. You only apply proficiency if you had proficiency with the original saving throw ability.

You can draw on your innate magic reserves to amplify the power of your spells, although doing so puts a drain on your body. When you cast a non-concentration spell using a spell slot of 8th level or lower, you can raise the effective level of the spell. Each level you raise the spell by inflicts you with one level of exhaustion once you finish casting; the spell's level cannot exceed 9, nor can it be raised to a point where you would exceed level 5 exhaustion as a result. If you reach level 5 exhaustion using this feature, you fall prone. Exhaustion gained from using this feature can be recovered from thrice as fast as normal (i.e. you remove up to three levels where you would normally remove one). Once you use this feature, you can't use it again until you finish a long rest.

Since their culture emphasizes "coolness" above all else, Crimson Demons tend towards chaotic alignments. They won't hesitate to disregard rules or societal conventions if they sense an opportunity to do something "awesome," although they are generally accepting of the consequences of their actions.