That. That right there is what a good relationship looks like. Healthy, pure, adorable.
I haven't heard this about this ship specifically, but people tend to go off on ships with age gaps, so in the event that someone reading this feels that way: Toko is TWO YEARS older than Komaru. Two freaking years. That's not that big of an age gap. Besides, Toko doesn't have her memories from the past two years, so in terms of maturity they're both Komaru's age. I'm not totally sure how old the two of them are, and if Toko was eighteen that would be a different story, but I'm fairly certain she's seventeen around the time of UDG while Komaru is fifteen or sixteen. (Feel free to correct me in the comments, but I'm just going to believe Toko is seventeen out of sheer desperation to make this ship work.)
They spend so much time together in Ultra Despair Girls that they actually become friends, which for Toko is a first, and Komaru becomes one of the few people that Toko can actually put up with. In the episode of DR3's Future Arc they're in, Komaru manages to talk Genocide Jack down from following Monaca into space (yeah, DR3 is really fucking weird), showing how much trust both of Toko's personalities have in Komaru. Komaru isn't scared away by Toko's general mean attitude and Toko isn't nearly as cruel to Komaru as she is to most people, which makes this one of the few Toko ships that could actually work.
Not to mention they're really fucking cute together.
Tokomaru gets an 8.5/10.