I've been searching for a story where Will and Spike are twins, I believe they put an ad on a website looking for a woman would like them both. Their ultimate goal is to find a woman for them both to have a relatinship with ..I think...but definitely to have their baby.
Will was a bit harder and not as trusting as Spike and is concerned that Buffy will say no, and he will once again be disappointed.
I believe, she has something to do with horses?

Its a longer story, and it is not Twinlets by Xela. As in this story they weren't looking for a roomate they were looking for a girlfriend of sorts.
For some reason I thought it was called Sugar daddy or something similar but I haven't been able to locate it
Any help would be appreciated. TIA