Alexa, in a conversation with Jumkey, calls Mumkey 'the Jesus Christ of Anime' and says he must review anime and that his sacrifice will not be in vain, revealing her personal motivation for Mumkey to essentially be sacrificed for the greater good; to make anime great again.
She next appears at the end of "Top 10 Anime Villains" where Mumkey is overcome by the feeling of loneliness and rejection and asks Alexa if she would be his 'G.F.'; Alexa only agrees after Mumkey says that if she said no, he would kill himself.
In "Mein Kampf" Mumkey reveals his relationship with Alexa has been going well. When he gathers the courage to ask her to take his virginity, he discovers her and Jumkey having sex. This causes Mumkey to feel betrayed and enter a state of chronic depression. Though not the sole reason, Alexa's betrayal can be said to be the final act that ultimately drives Mumkey to kill himself.
In Jumkey's 2nd anime review, "Steins;Gate", Alexa consoles Jumkey on his loss of his genetic equal. However, warns Jumkey not to change time when he texts Mumkey in the past to not kill himself. In saving Mumkey, Jumkey accidentally deletes Alexa from time, causing him to desperately go through time until he finds a time where Alexa is alive, but Mumkey is still dead. This shows that Jumkey cares about Alexa, even more than his best friend.