I'd be hard-pressed to find another series more mindless and sappy than this one; it's chock full of clichés, made little sense and had epic plot holes. That said, I was in the mood for something cute and really fluffy, and Hoshigari Love Dollar more or less did the job. If you ignore the pointless smut, that is. The only requirement to get maximum enjoyment out of this is to switch off your brain, because your mind will start whirling if you think about it for more than a few seconds.
There's literally no real plot. Basically, Omi falls in love at first sight with Matsuri and promptly chases her around for 2 chapters, wearing her down with his enthusiastic advances so that she agrees to get engaged to him and live with him. It's silly and senseless, but the remaining chapters are all filled with fluffy moments, obviously engineered misunderstandings (so that they'll once again "prove their love") and the requisite bed scenes. Yes, in every single chapter. Putting aside the fact that they are both 15-16, it's terribly unnecessary and actually ruins whatever romance was building. Having read all the oneshots and another of the author's work, however, it's obvious that this is her idea of being romantic, because I've yet to read a chapter without the couple doing it. Ah, well.
I rather liked Matsuri, the main female character; she generally gives as good as she gets, whether it's Omi who's earned her wrath or someone else. I almost cheered when a jealous girl dumps wine on her and bullies her, and Matsuri slaps her right back. Sure, Matsuri agreed to be Omi's fiancée too quickly, but it's pointless to expect anything in this story to make sense. Omi's childish self is also pretty cute.
Unfortunately, the ending was (if possible) even more ridiculous than the rest of the story.
The author had gone out of her way to show that Omi and Matsuri loved each other deeply enough to stand against any opposition, but then they let the one final obstacle destroy everything? It all ended rather well, but even the immunity to all this silliness that I had built over the course of reading this did not prepare me for being blindsided by that last development.
All in all, I really wouldn't recommend this unless you're in the right mood and feel particularly tolerant of idiocy. Hoshigari Love Dollar can be cute in its inanity, but there are plenty of better options for cute fluff that I would consider first.