Quite possibly most important... *how* did he fall in love? Assuming that we're trying for altverse rather than Massively OOC altverse... Snape's love
for Lily seems to be (to me, anyway) driven largely by his admiration for her intellect and abilities as a witch, plus that whole "oh, look! it's
another magic person!" What could Petunia have had that might have rouse within him that sort of admiration?
Alternately... we don't know all that much about Petunia as a young girl. Her marriage to Vernon, and the events of the wizard wars, might well have
dulled her. What if *she* fell in love with *him*... and then schemed to catch him?
How much would you have to change to make this plausible? How much would you be willing to change? "What if Petunia was also a witch, and Snape fell in
love with her?" requires less justification to get started, but seems ultimately a less interesting premise than somehow managing it with
Petunia-as-Petunia. (mind, there are plenty of excellent stories that come out of uninteresting premises... or even painfully overdone ones. For examples...
see everything Ozzallos has ever written.)
Hmmm... you could probably do some interesting things with the "Petunia as schemer" plan, combine with the fairly common "not previously
described binding ritual" (it's not even out-of-canon. Rowling created random plot-significant rituals out of thin air with some regularity) and
having Petunia pull the old switcheroo at the right time.... Of course, the long-term results would depend on the effects of the ritual itself, but it might
be interesting to explore.
for Lily seems to be (to me, anyway) driven largely by his admiration for her intellect and abilities as a witch, plus that whole "oh, look! it's
another magic person!" What could Petunia have had that might have rouse within him that sort of admiration?
Alternately... we don't know all that much about Petunia as a young girl. Her marriage to Vernon, and the events of the wizard wars, might well have
dulled her. What if *she* fell in love with *him*... and then schemed to catch him?
How much would you have to change to make this plausible? How much would you be willing to change? "What if Petunia was also a witch, and Snape fell in
love with her?" requires less justification to get started, but seems ultimately a less interesting premise than somehow managing it with
Petunia-as-Petunia. (mind, there are plenty of excellent stories that come out of uninteresting premises... or even painfully overdone ones. For examples...
see everything Ozzallos has ever written.)
Hmmm... you could probably do some interesting things with the "Petunia as schemer" plan, combine with the fairly common "not previously
described binding ritual" (it's not even out-of-canon. Rowling created random plot-significant rituals out of thin air with some regularity) and
having Petunia pull the old switcheroo at the right time.... Of course, the long-term results would depend on the effects of the ritual itself, but it might
be interesting to explore.