Toys 10: Shadow and Consequence
Rated: SO VERY ADULT
Warning: This bit has brief (almost off-stage) non-con, but not between Spike and Xander. Spike still loves his boy, and Xander is loyal to his master.
This is part of the Toys series. Spike was bored; Xander was there, but Spike always did have a habit of getting attached to his things. Each story stands alone.
Summary: A past mistake of Spike's comes back to haunt them, but when Xander turns to Angel for help, he may have made a choice that turns out even worse.