Psychologically being late night without sleeping is a disorder. Our deep mind started working that time so we feel that is the best time to talk serious stuff but it may lead you to Delayed Sleep Phase Syndrome (DSPS). actually it's bad. Really I don't know about whats the fact behind relationship It may be LOVE or friendship but it not depend on time. I sleep all day long and start working night it doesn't mean I'm in LOVE.
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