I have heard excellent things about this from Booksandlala so was very much looking forward to giving this a go. I will admit, the first like 1/4 to 1/3 was a bit shaky. I wasn't finding myself super interested in what was happening but that changed as Monstrillio evolved and the character perspectives shifted with a jump in the timeline. This ended up being very good indeed, and honestly kind of wholesome? The whole thing felt very steeped in family and connection and the end in particular felt very soft and warm which I was not expecting. 

Get you a family who will not only create a monster out of their dead sons lung, but love and accept him as their own

and cover up the two murders he does and then say goodbye to him as he returns to his true monstrous form. Have your father who was so afraid of you learn to be soft and gentle to spiders because he knows what it is to love something monstrous.

Frankly the more I am thinking about this, the more I loved it!