Ok, I find this better than Starspeaker, but it still doesn't make sense to me that much. Sunny seems fine as a single.
It has basically the same personality match as Starspeaker yet the love Starflight had for Sunny was longer lasting. If Sunny didn't reject him, and actually loved him, this would be perfect.
Except for the fact that they are basically siblings, and even though they aren't biologically, it still feels like they are close to siblings.
That being the only problem, I'll rate it a solid 5/10
Pros: Cute, personality match, starflight has been in love for a long time
Cons: too much like siblings
Overall rating: 5/10