Be sure to see replacement glyphs of 閒 and 閑. Not likely「gateway to the Sun」unless perhaps if considering the Sun as some divine goddess of a sort, flashing, blazing, shining brightly, and if so, then「day, portion of a day」「within that gateway」to the special zone of a town, the quarter where the service providers ply their trades, an INTERVAL of measured time or in a specific space…'interval' in English literally means「inside, entered」into the「vale」and vale is the gorgeous space (that is, a small gorge) between what is「raised on both sides」not unlike various places available as short-term rentals located on the person of a service provider. An INTERVAL OF TIME that passes, the timing of client access to services, data necessary for billing data per individual client, or as time and motion data for benchmarking and management by the shaman of the service-providing employees.
　Formerly in Chinese suggesting a NEED FOR SEPARATION and being DISCONTENTED because of interference, positioned TOO CLOSELY TOGETHER and DEPRIVED OF COMFORT, a NEED FOR THINNING OUT the clients a bit, with the inner element either as「two orifices in contact, juxtaposed female-to-female」and therefore being too close together, or,「speaking」that may be disturbing the neighboring room occupants. Referring to the missing GAP, INTERVAL or LATERAL SPACING. Concept of SUFFICIENT SPACING, ROOMINESS in which to move freely applies directly, since colliding with an adjacent set of bodies might limit activities, and no one appreciates being struck by an errant limb.
　Glyph 閒 is used as a replacement, not because it means「gateway to the Moon」but because it means「gateway to meat, leisure, mooning」and the mooning position reveals「two orifices properly spaced」and separated by the perineum wall, or some interval of time. 閑 as「woodies in the gateway」also needing sufficient SPACING of time and distance.

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: gap; to separate; to thin out (seedlings); to sow discontent; between; among; within a definite time or space; room; section of a room or lateral space between two pairs of pillars; classifier for rooms
Japanese: space, gap, interval, distance, time, pause, break, span, stretch, period, relationship, members, due to, because of, period of time, among, between, inter-, 1.818 m, counter used to number the gaps between pillars, room, while, during, occasionally, now and then, sometimes, slow, stupid, thinning out, pruning, culling, sub-sampling, infanticide, lucky, partition between two rooms, room divider, partition wall, tedious, sluggish, dull, irritating, to be in time for, to serve the purpose, to be good enough, to be enough, intervening
Unihan extended: interval, space; place, between
EDRDG: interval; space

Used within names (nanori)
ちか　･　は　･　はざ　･　はし