Dandadan, Vol. 10 (manga)

To avoid being late for school on Vamola’s first day, Momo takes the mysterious kaiju girl on a shortcut through some off-limits ruins. But the protection spell they perform doesn’t work, and she runs into the slit-mouthed woman who resides there! The two narrowly escape, and it’s only later that Momo realizes the real danger they were in. So why is it that for Momo’s own safety, Seiko is now forbidding her from leaving her room after 10 p.m. for the next week?!