This is the softcore ecchi that I've been missing in my life. Everything else I've been reading is either too tame (though I do like wholesome ecchi like Anjou and Dosanko Gyaru), or WAY the hell too perverted and extreme. Yuuna knows how to tiptoe the line, and with gorgeous art.
If this doesn't have a "true" harem ending, it would not surprise me if the alternate future Kogarashi's are brought into reality by splitting Kogarashi's soul...or something. Hard to say at this point.