Just read the last book of the series and I can say it has a subtle backstory that's explained here and how has everyone still misses each other in spite of the way they parted. It's not a pure HEA (happily ever after) but everyone gets to be with who they wanted and that's the idea. Steamy sex, of course, does count if you are fan of threesomes.Will only purchase purely for the sex scene and Ai's character growth.