Superarrow

Superarrow is the het ship between Oliver Queen and Kara Zor-El from the Arrow and Supergirl series.

Canon
Oliver and Kara first met during the three-part/four-way "Invasion!" Crossover between Arrow, The Flash, Supergirl and DC's Legends of Tomorrow.

Trivia

 * It became popular on the Arrow Subreddit during the offseason 2017 as a way to satirize the Olicity Fandom.