My answer was not accurate enough. According to my knowledge of online literature, there is no description or mention of a 70-year-old woman named "Kang Kang". You might have remembered the name or the plot wrongly. If you can provide more information, I will try my best to answer your questions.
In many comic storylines, Kang takes on the role of a timekeeper. His ability to control and manipulate time makes him a significant and complex character.
Kang wasn't typically black in the comics. Usually, his character was presented with other characteristics. However, the comic world is diverse, and there could potentially be an exception I'm not aware of.
I, this little fairy, have some recommendations. There are I Am the Fourth Generation of the Zheng Family, 1719, and The Virtuous Concubine of the Qing Palace. These are all BG doujinshi novels with Kangxi as the male lead. I hope you like my recommendation.😗
Kang's demise in comics is a complex matter. It could be a result of a team-up of heroes, or it might be due to an unexpected turn of events involving multiple characters and their actions.
The identity of who defeats Kang can change from one comic series to another. Sometimes it's a team effort by multiple superheroes, and other times it could be a lone hero with a strategic advantage.