"I love Aino."
A little bit. Having that word order emphasises the person who is the target of your love (Aino, sinä, hän). :) Having just "Ainoa rakastan" feels odd though. If you add to the sentence it works much better, although it's still much more poetic than "rakastan Ainoa".
Finnish is heavily a theme-rheme language, that is, begin with the topic and then tell something about it. Therefore originally one said Ainoa rakastan, but because of Indo-European influence subject-verb-object is nowadays considered as the neutral word order, i.e. Rakastan Ainoa.
All Finnish names end in a vowel, so adding any suffix is a no-brainer:
- Rakastan Ainoa (← Aino)
- Kysyn Juhalta (← Juha)
- Katso Annikaa (← Annika)
However there have always been foreign names in use in Finland, Swedish, German, Russian…, and these often do not end in a vowel, Mats, Henrik, Birgit… To ease pronunciation of those when a suffixe is added, you put an extra -i- (and sometimes double k, p, or t before adding that -i-):
- Rakastan Matsia
- Kysyn Henrikiltä
- Katso Birgittiä
So Rakastan Luisia.
This system is generally applied to all person names, even if it ends in a consonant that is not pronounced in the original language, e.g. French Jules → Rakastan Julesia.
If a location name ends in a consonant that is not pronounced in the original language, e.g. French Versailles, a different rule is applied (advanced topic).