You are Rumia, the Youkai of Darkness
A few nights ago, you ended up having quite the adventure, which had you meet many new faces, and ultimately, along with Wriggle Nightbug, retreived a stolen Tomb from Hatate Himekaido, who had stolen it from Marisa.
This act garnered you favor with the residents of the Scarlet Devil Mansion when you returned the book, which contained the secrets of the Scarlet family, which Hatate was going to publish, as well as Reimu Hakurei, who you found the Tomb on behalf of.
That was when you realised maybe leaving the Forest and the Misty Lake every now and then is good! There's others than Wriggle, Cirno and Mystica out there, and unlike what you thought before, they're not all unreasonable Shrine Maidens that attack you on sight; even the Shrine Maiden isn't!
Oddly enough, ever since you returned the Tomb, you can see within your own sphere of Darkness. You have no clue why you suddenly gained this ability. Wriggle thinks it might be linked to something that happened during your adventure, Cirno thinks you just opened your eyes, and Mystica thinks you've just overcame night-blindness, which she always blamed herself for. It's sure useful not crashing into trees anymore!
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> Over to you