I know people who can possibly be ISFj. ( acc
; pro
)
They can be friendly, but
element can make them somewhat assertive, or in certain cases agressive.
For example, my father is possibly a cp6-ISFj ; he tends to be really reckless and capricious, or agressive when his desires not met.
My sister, probably 4-ISFj, is a friendly, modest woman, but his
can make her excessively relativistic; In times I insulted her of "progressive hippie", insult which she took somewhat kindly... Socionics taught me that being a F-type is not a weakness, but only a difference.
I think agressivity in ISFj-types is related to
information element, but also in belonging to some enneagram categories, especially 6 and 8 ; it can be also related to the RED vMeme.