The worlds seem to run on the same time frame. No one complains about the MC being gone "unusually long" -the complaint in this chapter was only because he'd been in the other world several days. And he doesn't cross between worlds to find only a moment, or conversely days or weeks, have passed in one world or the other. Narnia Time certainly doesn't seem to apply.
The Galactic Navy Officer Becomes an Adventurer
by Takuma Tomomasa , A_Itoh
Available on mangabuddy for reading, and for sale at https://www.amazon.com/dp/B0BT6V7CMM
by Takuma Tomomasa , A_Itoh
Available on mangabuddy for reading, and for sale at https://www.amazon.com/dp/B0BT6V7CMM