Unlike a few shows that try and mix and match characters of such opposite ends, like how well the MLP universe and the artists create alot of these possible what if moments so very well in their lines.
That for sure feel what you've done here xXMentalIncXx, how clearly you light the fire of SweetieBell to Spike and give nothing more than the close interaction of the two for the benefit or showing some attraction between them, who said it only ever needed to be done with just a kiss?
Even then you do well to take the MLP look and give it some realism and better depth than just the show would have. Spike himself looks much more fleshed out and much less pudgy as she always seems and even more the gentlemen's bow is very responsive how human it looks and how it compares to the feminine glow of SweetieBell.
Like best how well you take such creativity with your lighting here, its the best part of the image. Clever using not just the fire alone to win the hearts and attention of the fans but even the glow itself and how much it compares the warm feeling between these two, well done.
And nice job too with the lighter things you seems to take your time to add from the blush on the faces, the wonderful shine coming from SweetieBell's eyes to even how the small parts of the flames emit form the note like something with flames would be, gorgeous.
Plain to see you know your skills and how to apply your talents, best you keep up the incredible artwork xXMentalIncXx ^-^