Spoiler alert!
.
.
.
.
.
.
It's actually intentional by the author, little mushroom is often depicted as a "bystander", someone who's merely an onlooker to horrors unfolding to a community he has nothing to do with. He only went there to find and rescue his spore .
And if my memory serves me right, Lu Feng will even bring up to An zhe, how he feels An Zhe's an onlooker, he's detached from the dire situation hummanity's in, because simply he's not human. That's one of the reasons why Lu Feng was suspicious of An Zhe's. He questioned his reactions.
An zhe does feel bad for the human race, he feels pitty for them, he's sorry for what they're going through, more so what's Lu Feng going through, but at the same time, whatever's happening has nothing to do with him, doesn't affect him the same way it affects the race involves.
MAJOR SPOILER ALERT: Even when he finally figures out where his spore's located and he rescues it
He just gets the f out there (or atleast tries to), he's achieved what he came there to do and he has no reason to stay.
Hope it made sense (๑•ㅂ•)و✧
also I recommend you read the 2 books! It fills a lot of the gaps the manhwa might have dropped, and honestly the world building's insane. It's such a rich intricate plot. *chef's kiss*
Spoiler alert!
.
.
.
.
.
.
The chapter An zhe finds his spore in, is the final chapter in Book 1/Volume 1, and then after that, there's still the entirety of book 2 xD
Their romance is book 1 is slow af, it picks up in book 2, tho i'd still consider it slow xD
Anyway, by the end of book 1, and in that final chapter, it's made clear that An Zhe's taken a special liking to Lu Feng, though that moment of clarity and understanding comes at the final chapters of book 2 (for both us and An Zhe) and xD it unfolds in the most beautiful and heart wrenching way, like every puzzle piece starts satisfyingly falling into place and you connect the dots and are like "Oh..OH!" the books and writing's soo good xD
(I wrote it extremely vague cause I'd be spoiling the literal ending of the entire story, and I am not about that )
Furthermore, I wouldn't really say that at that point in the story (an zhe finding his spore) either one really "likes" or "loves" the other, but they're both definitely special to each other, interested in each other. Nobody's ever treated Lu Feng the way An Zhe has? also the fact that he's still suspicious he's not human, makes lu feng pay alittle extra attention to our little mushroom
Something's scratching his brain, but he just can't put his hand on it xD
Anyway yeah, the romance's pretty slow, but it exists dw xD
The only thing I can't get over is the fact that the MC is emotionless to everything. It's unsettling despite understanding that mushroom is not a human to begin with.