The Phoenix Sorcerer from Unearthed Arcana: Sorcerer has the feature Mantle of Flame, which allows you to "wreathe yourself in swirling fire" for one minute. One of its effects is described as follows:
Any creature takes fire damage equal to your Charisma modifier if it hits you with a melee attack from within 5 feet of you or if it touches you.
What does "touches you" entail? Do unarmed strikes count as touching?