I LOVE your breakdown! I just wanted to add as well that I think Taku is the youngest out of all of three? I think that lack of maturity in relationships and messy emotions also played a part in his personality and how he came across. I didn't think he was manipulative per se as some people have claimed in the comments before, but I did see that he became more desperate and earnest towards the end when he realised he had strong feelings but that it was also too late to recover anything between himself and Haesoo.
yes he is the youngest! and the only one out of them to not experience a first love at the start of the story. because joowon and haesoo were each other's firsts. i personally do think he's manipulative, but not in like a crazy kind of way. as this emotionally detached photographer kind of character to begin, i think he tends to purposely push certain emotions that he wants to see out of others. by the end though, he was definitely less composed.
I don't necessarily think he was scheming or 'enjoyed' seeing Haesoo in pain, but I think it's more like if Taku knew things weren't going well between Haesoo and Joowon that means he has a chance, so seeing Haesoo unhappy meant he instead could be there for him. I think there's an element of emotional deceit there, but not designed to hurt Haesoo, more like expecting his other relationship to fail so that this one could succeed. Which, you know, in human nature that is a very real emotion and happens all the time and I love how the writer captured it here, because it has more depths to it than your usual jealousy plot.
So I read the author's notes about Taku: aka one of the most interesting characters I have read in a while (haesoo and joowon are too. thats what makes LOH so great). And I was very satisfied to see that my thoughts about him aligned with what the author intended to portray about him.
I can't help but think back on whatever i had thought/written about him (but also some stuff which I missed), just as the writer talked about in their end notes:
1. Like as I said in previous comments: Taku saw his romantic partners as photography subjects, and viewed life from behind the lenses instead of living in the present. He believed he could stay an unaffected outsider (ie: an observer behind the lenses) within these relationships and thought he was invulnerable to heartbreak. I did however never make the connection that this rooted with the fact that he always felt like an outsider wherever he went. aka mixed kid problems I believe. Idk if yh ever clearly highlighted this or it just went over my head, but now that its been explained to us, it makes SENSE :o
2. He also saw relationships as nothing more than candy all of the same flavour: he liked the sweetness of it while it lasted, but when it melted away it didn't really matter as it wasnt memorable or distinct for him.
3. He initially saw Haesoo as another photography subject, wanting to see how he can affect Haesoo. He tried to purposely draw out different emotions from Haesoo (ie: what people mean by when they say he's 'manipulative'), especially for his art. He didn't approach Haesoo out of love or sincerity, but rather his advances were out of his mischievous/curious nature and his desire to read the rest of Haesoo's story. The author said he desired to "witness change" though, which I never fully thought about. So he wanted to change Haesoo, or affect him in a way that influences change. But thought he could stay unaffected? hm.
4. Haesoo ended up changing how Taku viewed relationships, and how he viewed HIMSELF within relationships by experiencing heartbreak for the first time. His 'cool and detached/unaffected' artist persona crumbled due to him getting attached to Haesoo.
5. I liked that the author added that in future relationships he stopped thinking so much about himself and cared more about his PARTNERS' feelings. Because honestly that was what was striking about Taku with Haesoo. He was really quite selfish? He never truly seemed to care about how Haesoo felt. Like, yes: he was very AWARE and observant of how Haesoo felt-- aka something Joowon/Haesoo were very bad at with each other lol. But despite his observant nature, Taku used that opportunistically and truly only did things for his own benefit. Like trying to take advantage of Haesoo's heartbreak, or in other words 'bury into his void' just for curiosity as an observer. So I understand from the author's note now that Taku being selfish even at the end of the story was clearly on purpose. I think yh wanted to show how inexperianced Taku was in serious relationships, through this selfishness of his. But that his heartbreak would serve as a point of growth for him in future relationships. Cool cool.