I managed to get Kaius, Lucan, and Ryuu's ending, so here's my feedback:
I enjoyed playing it, I really did. Kaius's path was the most fun, with Ryuu coming second, and with Lucan being extremely bland and boring (and I love the sweet, shy kind of guys!). I actually preferred the art of the demo than the art in this one, there's something not quite right about their eyes a lot of the time (Marin and Ryuu's eyes are too far apart for example), and the CGs are rather inconsistent in style.
The story could have been a bit more important to the game, because otherwise it was really just following a boy's path and discovering his dark secret or something. Despite Marin being able to read people's minds, this didn't come into play enough! There were so many things you could do with having her hear the boy's thoughts (with the exception of Kaius, which would have created even more interesting situations), but it was barely mentioned in passing every once in a while. Such a shame!
So anyways, here are my thoughts on each boy's path:
Like I said, I had the most fun with this one, and it was also my first path that I took. I did enjoy the fact that he was just really shy and sweet (more so than Lucan was supposed to be), and most of his scenes were pretty damn 'awww' inducing. The scene in which he thinks Marin is asking for sex instead of a kiss is really cute, my favourite part of the entire game.
There were however inconsistencies with the storyline. For example, right after he mentions that you're his first and only friend, the scene in which he and Ryuu fight comes up not soon afterwards. Marin then mentions something along the lines of not wanting to break them up because she's not really that much of a friend with them (even after that whole 'I want to be your friend!' scene with Kaius).
This is because the fight between Kaius and Ryuu is a general scene that plays in every single path you take, but it becomes really inconsistent when you take Kaius's path beforehand. For example, Marin should be rushing to the rooftop to stop the fight instead of being meek and wanting to take a backseat. It really annoyed me to see her act as if I never even interacted with Kaius.
The second inconsistency is at the end of the game when Marin loses her power and has to leave Planets. She says goodbye to Ryuu, Lucan and Haruhi - but not Kaius who was supposed to be her boyfriend for god's sake. Not even a "Oh, I'm leaving, and since I think I'll never see you again, let's break up.". The fact that Kaius comes and visits her later on is even more awkward when she mentions she really didn't think of seeing him anymore, despite going through all that drama together and telling each other that they love each other. It was inconsistent, there should have been more of a dilemma of Marin not being able to see Kaius anymore on a regular basis - or even having talked to him in the first place before leaving.
I also think that Kaius killing his mother would have been much better if he merely hurt her, a lot. If he really killed his mother with his power, the scene with Marin wouldn't have played out as it did, because he would seriously stay away from her and even become paranoid of losing control of his psych around her. Now, if his mother was merely hurt, then he would be more comfortable with staying with Marin.
Oh, and that day when it was raining, I figured you two would rush off to see if the kittens were fine! But they never get mentioned again, that's kind of cruel. Especially when they went out on a date to buy a kitten when there were wild ones that he was already taking care of ...
Despite the inconsistencies, Kaius's path was the most entertaining as well as romantic and sweet. He's also my favourite character, but I might be biased because to me, a redheaded shy guy = instant win.
Ryuu was my last path (simply because I am much more fond of the shy/sweet guy, so I went after Kaius first, then Lucan), but he was rather fun as well. The weird thing is, is that you do not ever confront Ryuu about Kaius. He's always trying to pick a fight with Kaius, extremely so, but it never gets addressed in his path. There was a brief mention of it, with Ryuu almost wanting to tell Marin, but then changes the subject and it's never brought up again.
I also think that, if you went for Ryuu, instead of pushing Kaius off the rooftop, it should have been Ryuu himself that was pushed off, then he could teleport himself with Marin to safety and the story could continue. It would make more sense to me. Again, just like Kaius's path, Marin showed little interest in breaking up the fight despite following Ryuu's path. Inconsistent, again.
I must also mention a huuuuge reality error in Ryuu's path. The day he wants you to skip classes with him because it rains, the two of you stay out in the rain until you both catch a cold. I must smack you over the head because you do not get sick by standing in the rain. You get colds/fevers because a virus has passed around and you have come into contact with it. Rain doesn't cause viruses, it might cause pneumonia if you stand in it drenched for maybe 3 days without warming yourself up, but otherwise rain is quite harmless. Not only that, once you've gotten a virus in your system, it might be a week or two before the symptoms (aka; runny nose, rise in body temperature etc) actually show up.
This is really a huge pet peeve of mine because Japanese manga/anime love to use this cliche to get a character sick, when it's obviously a myth that you get sick because of the rain. You simply copied what they did. Despite the story being centered around weird powers, seeing this unfold really ruined my suspension of disbelief.
Anyways, aside from that it was alright. Ryuu was fun and his backstory was sad, but I didn't pay it much attention. Surprisingly, his fangirls never came into the picture even though he was as popular as Lucan.
Lucan was my second try because I love shy and sweet guys. Lucan was not that guy. He was simply a homemaker, the boring type. The one that makes food, and takes care of his siblings, and has nothing else to talk about because he has no personality, and this is his entire life.
It was a bit interesting in the beginning when you had to save him from fangirls, but when you actually spend time with him, it was blah and uninteresting. In fact, I skipped through most of the dialogue. I couldn't care less when I saw him imprinting that girl, and I barely remembered what happened in the end (I think he got expelled?). All I remember was that now you had to take care of his siblings as well, blergh, horrible ending.
Also, that part about Ryuu liking Marin as well came completely out of no where, especially if I'm focused on Lucan's path and avoiding Ryuu like the plague. I see it as a desperate attempt to give Lucan's character more depth, but it made him even more annoying to me.
So yeah, Lucan was definitely not my favourite guy, and I had no fun following his path.
Now that I have played through all the paths, what perplexes me is:
I first played Kaius's path, so to me it was only natural that Marin invited him as the 5th person to go to on a field trip or something, because she wanted to be his friend. However, after playing Ryuu and Lucan's path, I found this unnatural and didn't fit with the story because Marin wouldn't like Kaius enough to invite him. Especially if you were on Ryuu's path, she'd have avoided him because she knows the friction between them.
These general scenes that don't change gets annoying after a while, even if it was just tweaked a little bit to reflect the path you've been going for it would have been a much nicer read.
I don't think I'll go for Haruhi's path, since he's 13 years old and dresses like a girl, so that really doesn't interest me at all.
Anyways, it was still a fun playthrough, with the exception of Lucan's path, and there were three instances where you spelled 'sight' wrong and wrote 'site', but regardless of those faults, it was fun.