@ZhaoZoharEX  
Me either. All I’ve seen are the trailers.
 
Mainly I just think it’d be more poignant that way.

@Background Pony #4994  
@Scrounge
 
I haven’t actually seen Rainbow Rocks yet outside of small sections so I can’t form a proper opinion.

@Scrounge  
Hmm, could be.

@Background Pony #4994  
I like to think she didn’t realize what she’d had until after she had her change of heart, and by that time it was long gone.

@Scrounge  
Personally, I don’t believe Sunset when she says she didn’t really like Flash. She was visibly depressed when Rarity commented that Flash was smitten with Twilight.

@Scrounge  
You bring up a good point. The only counterargument I can think to that is if she took her studies seriously like she did, she at the very least respected the princess. Celestia might be partially to blame in this case because she was the one who presented the mirror in the first place. Had she not done that, it is possible Equestria Girls might not have happened (which depending on who you ask may or may not have been a good thing). It is also possible (albeit less probable) that the series of Friendship Is Magic might have played out differently if those events didn’t happen.
 
I guess the key word here is “variable”. Let’s face it, Sunset Shimmer is pretty much an analog to Twilight; Sparkle was reclusive for the most part but still held family (Shining Armor, her parents, and even Spike to a degree) in high regard. Sunset may have been arrogant and self-centered, but that doesn’t mean she’s like that all the time and for all we know, her relationship with Flash as siblings may have been similar to Shining and Twilight.
 
However, the opposite could be true as well since Sunset was presented as an antithesis to Twilight. But if we are going along with the forementioned argument of why she sought out human!Flash when she had the chance, I’m willing to bet she at least decently loved her brother.
 
Again, this is all just speculation involving a film that already has a lot of plot holes. That doesn’t stop people like me from having a bit of fun. :D

@ZhaoZoharEX  
Point taken, and Sunset has stated she didn’t love human!Flash, so I guess it’s safe on that account, though obviously that falls into the category of her being kind of a bitch back then, which is also canon, so it works out I guess.
 
I guess the biggest question is if she’d have treated her family any better than she treated everypony else. If we’re taking that comic as canon, she basically thought Celestia was beneath her, so her brother might not have been worth her time.

@Scrounge  
I’m not saying it isn’t, but think about this for a second:
 
Supposedly in the comics, Sunset never sought any friends, saying (rather arrogantly) that “she has better things to do than socializing”.
 

 
For the sake of argument, let’s say for a moment they really are siblings in canon (which I’m assuming they aren’t). Assuming the sibling relationship is good like it is between Twilight and Shining Armor, it would make sense to seek out relationship (friendship or otherwise) with someone is by all accounts her brother. They may not be complete counterparts, but they are essentially the same person as you said. If she is in a world unfamiliar to her, this relationship helps maximize survival.
 
And things between the two worlds are not completely the same. Spike being a normal dog instead of a sentient dragon, Celestia being a normal principal instead of a ruler, etc. So while they may be siblings in Equestria (or at least this little insignificant headcanon I like so much), the same may not apply in the world beyond the mirror.
 
With all that said, while I cannot completely defend Sunset if she did really love human!Flash in a romantic context, it is hardly the weirdest thing out there considering she turned into a freaking demon in the film.

@ZhaoZoharEX  
When it gets to the point that you can say they’re essentially the same person, then it becomes weird.

@Scrounge  
It’s not uncommon people to seek partners similar to family they know, some more than others.
 
I should also mention this was made for an AU fanfic.

So when she ran of to the human world and wound up dating the human version…
 
That’s kinda messed up.

@Cirrus Light  
I can relate.
 

Oh, and this is relevant

@Cirrus Light  
This was actually drawn with an upcoming fanfiction project in mind. It’s an AU where Twilight, Trixie, and Sunset were all childhood friends and classmates in Celestia’s Magic school. Sunset and Flash are half-siblings who share the same father, but not the same mother (Flash’s birth mother is Sunset’s stepmother).
 
Here, they both have a career in the Royal guard where Sunset was recently promoted to captain as Shining Armor’s successor.

I liked it thinking of them as a couple. ‘cause usually when people draw couples (especially in bed O.o) they make it very sexual and all, but the funny reality, in stark contrast to the common fictional depictions, is that this is more what it’s like to be married than that >.<

@YetAnotherBrony  
Got a similar headcanon myself, in which Lightning Dust and Flash are siblings.
 
This pic is still adorable nonetheless.

While I don’t subscribe to this particular headcanon, I do have a similar headcanon where Braeburn and Spitfire are half-siblings.

@Remetheus
 
@Remetheus  
Brb, gonna go bake a portal.

It’s not creepy!

@Background Pony #D3B0  
I’m not entirely pleased with how I made Sunny’s left hoof. It just seems too off and too short to me.
 
 
@Millennial Dan  
Five minutes later  
Sunset: Flash, why are you sleeping on the floor?
 
Flash: Because you knocked me off.

Interesting head-canon.

I just think it’s cute how Sunset is a crazy sleeper here who bops him while she’s dreaming.

Also, it looks like Sunset’s got the ol’ jimmy hooves.

@Background Pony #D3B0  

@ZhaoZoharEX  
@Ciderlove
 
Ladies, gentlemen, please! They can be both!