Final hooked stroke is the 乚 right-form of the 乙 radical and is why 也 is filed under 乙. It is also the visual tail that closes the coiled-snake or basin shape; the curl gives the whole char its rightward sweep.
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也yě
also; too (upper fused portion)
Upper two strokes are a fused remainder with no standalone CJK identity; historically 也 depicted either a water basin or a coiled snake, and these strokes outline the body of that shape. Modern teaching treats them as an indivisible top stub.
