... Oof...
I said it once, I say it again. Sierra really is the best writen character. It's so real it's crazy. I believe the mangaka either consulted people, investigated or something. You can see how she digs deeper and deeper into denial. "He's just using you". Even she recognizes it's normal. He IS just a host after all. When she tries to get support from him, of course it doesn't come. Then he sees him with another woman.
Now she's there: With a face half tired half scary, desperately fighting to make her illusion a reality, or at least keep it afloat. With bags under her eyes, puffy eyes for all the crying and puke smelling breath. She's really going all or nothing in this one.
I choose to believe it's because she, deep down, would rather her illusion breaks and accept reality. You can see she's divided in her inner monologue.
On one side, I like this series. On the other, I feel pity for Sierra. On the third hand, this has to end somehow. I don't think this will last much longer. Masato either gets stabbed/traumatized and shuts himself OR stays with AT MOST the 2 uni students. Why?
The rent lady has no romantic feelings for him. 2 girls are way underage and Sierra is... yeah.
...I hope she get's her happy ending tho.