i think what happened at the end was hallucination (or shinpei died and they reunited in afterlife).
reason is because at the panel they're hugging at the end, suddenly there are so many flowers around the house. (i checked and those flowers are cosmos, in hanakotoba means "harmony, peace")
then on the next panel it zoomed out of the house, and there really were no flowers around the house. and even in previous scenes, where shinpei visited the house but didn't enter, or any other scene, there were also no flowers.
can't say if that really means anything, but i'm sure that implies something.
i think what happened at the end was hallucination (or shinpei died and they reunited in afterlife).
reason is because at the panel they're hugging at the end, suddenly there are so many flowers around the house. (i checked and those flowers are cosmos, in hanakotoba means "harmony, peace")
then on the next panel it zoomed out of the house, and there really were no flowers around the house. and even in previous scenes, where shinpei visited the house but didn't enter, or any other scene, there were also no flowers.
can't say if that really means anything, but i'm sure that implies something.