>>4665
>Last night was an... Experience
Yeah I too had things like that what you describe and the funny thing back in the ancient times this experience was common now it is almost unheard nowadays.

So... where to start.
In Shinto and similar traditions where you are not just work with spirits but maintain the balance between the worlds usually you get helper spirits. Sometimes they belong to the land to the god or represent some parts of the tradition. While some of them grant abilities or insights some guidance while some sorta works as a "company spirit". Company spirits have the ability to learn and adapt with you. And 1 important ability that was extremely important for the "priest caste". Finding them between lives and returning to them "what they learned already". You see we have an inclination to do the same things we did in our past times so it is quite useful that instead of wasting decades regaining our skills a companion spirit brings it back to us "when we are ready"
Truth is it was weird for me that you are able and remember speaking japanese in your dreams. I mean if you were extremely fluent in it already and most of your thinking processes were japanese it would be okay because I too think and dream in different languages but only in those that I have learned already. Other languages get auto translated usually. But then again now that my mind is expanding I too get different languages bringing me strange concepts that have no translation.
>body being slightly smaller
I too have a "Shinto body" and mine is also smaller in stature compared to my usual and IRL forms
>she either possessed me or assimilated me or something
She "merged" with you. It is a different being but it is also (You). The reason why your sisters were worried because it is not exactly you but it is like your dog. It's your dog but if you don't recognize it as "yours" or the dog doesn't consider you it's "master" problems may arise.
Maybe now you can access it more easily. Try to "call it" while being awake. But as always take it easy with things like this because sometimes you can access it only if your "energy flows" as stable as they were "back in those lives". For me it feels like a memory companion spirit. I am not feeling an authority from a higher god within it. I think this one is yours.

>after this happened they seemed pleased for some reason
<Because you are worthy of your former glory sister
this is what they said