First, thanks so much for contributing a Katie story to Romantic Spanking Month! It's a welcome addition to this month's offerings and I know Sunflower and everyone else will be tickled to see it.
As to the story, I think it was clever to use Phil's An Alternate Proposal, here in an alternate reality where it's a movie, as the catalyst for events. (It was a nice touch to use Phil's signature drawing as the cover art for the DVD
). The eventual spanking was very well-done, bare-bottom and reaching a satisfying climax. I enjoyed Katie addressing Bullmoose as "Sir" which in this context strikes the reader as more erotic than disciplinary (because of Katie's evident submission to Bullmoose). It was certainly romantic enough to fit in to the spirit of Romantic Spanking Month 
. The only "problem" is the eternal conflict between eroticism and humor: note that in order to make the spanking more erotic than the typical Katie scene, it was necessary to sacrifice the usual sources of humor, namely, that Katie's the last one in the world to realize that she's going to get spanked and that she never does realize how much all her various spankers enjoy having her OTK. The trade-off was justified here since the story was supposed to be romantic.One other problem I think was Bullmoose's hypothetical proposal and the subsequent sudden rift between him and Katie that it created. Now it's certainly possible for people of that age to behave like kids sort of playing at love and romance, and it might even be that this would not conflict with the Bullmoose and Katie we already know, but it did affect the emotional atmosphere of the strip, suddenly changing it from light romantic humor to something more serious - only to be changed back again. Without some sort of transitions, the effect was slightly jarring, but I don't mean to harp on it, especially since providing such transitions would have required a lot more time. One possible alternative would have been to have Bullmoose's proposal be serious from the beginning - a few carefully-chosen words just before could have provided the necessary transition. The proposal at the end of the light musical comedy Gigi comes to mind as an example.
Now on to the substantive question of where the engagement leaves the strip. Katie's plots are generally driven by the series of risky situations she gets herself into ("risk" meaning here the risk of her getting spanked), while the humor, as noted above, derives from the fact that the reader knows Katie is going to get spanked long before Katie herself does, thus allowing a build-up of anticipation. It seems to me, therefore, that Katie's engagement to Bullmoose should be a neutral factor relative to the usual drivers of the strip, neither helping nor hurting them. Perhaps the threat of a spanking from Bullmoose will hang a bit more heavily around Katie from now on, but that's all.
The only thing that worries me is that since Katie now realizes Bullmoose likes spanking her, it's important she never get wise to just how much pleasure other males get from turning her OTK. Some strips have been hurt by engagement/marriage: Li'l Abner comes to mind here, as in the mid-50's (I think it was 1954) Abner finally married Daisy Mae. But in Abner, one important source of humor was Daisy Mae's sexual frustration at not being able to get that lunkhead Abner to pay any attention to her, and there was never anything like that in Katie, who can still get in trouble both on the job and at home with Bullmoose
.
..................and what better cover for the DVD than my logo 
. a love story with a spanking, who could ask for anything more indeed 
. saaaaay! that's a pretty happy look on Katie's face in panel 11. there's that happy ending that Sunflower made reference to 
