We see the same usage in Hokkaido, but if you’re speaking with friends or other casual acquaintances it’s more common to say “Suki/koi ni shihareta”, which translates roughly as “He/she (the target of our subject’s love) had herself get fallen in love with”.
What about 愛します ai shimasu? In which context would you use ai shimasu? Where does it fit in on the spectrum of politeness, deference, indirection, etc.?
I’m actually pretty sure that you can’t say ‘ai shimasu’, since I’m getting an ungrammatical reading for it… “aishiteiru” is a very, very idiomatic expression, and despite the fact that you can conjugate the ‘suru’ in practically every possible form, if I try to use the polite ‘shimasu’ I instantly get an alarm bell insisting that it’s ungrammatical. (on a similiar note, if I say ‘koi shimasu’ it doesn’t seem ungrammatical but it also doesn’t mean anything.)
Ok, I was just reading a book this morning that had a great example of “suki desu” and “aisheteiru”. Here’s the passage in romaji:
Shinobu & Suguru are in a passionate embrace. (told you I read torrid crap)
Shinobu: (whispering to Suguru) Suguru-san, daisuki da (Suguru, I really like you)
Suguru: boku mo (me too) aisheteiru yo (I love you)
Shinobu: a…ai? o…o…ore mo! * (lo…love? ME TOO!)*
I should note that Suguru is an adult in his late twenties and Shinobu is a senior in high school. (without getting into ethics, this is a really common age pairing in Japanese romances) So Suguru uses “boku” but Shinobu uses the rougher “ore”.