I Think When Pein Said We Are Pein..He Is Reffering To All Of Them..The 6 Paths Of Pein..
Anyway..Yahiko Cannot Be Pein/Nagato For Some Reason..When Jiraiya Mentioned The Name Yahiko To Pein..Pein Replied That "Ah Yes..I've Heard That Name Before..He's Been Dead For A Long Time"
Here's The Proof..
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I Think It Is 100% That Pein Is Nagato..As You Can See Here Pein/Nagato Calls Jiraiya Sensei..Which Means He Is A Student Before Of Jiraiya..
Here..
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