Unexpected Relative Phase while making the Toffoli Gate

I was trying to build the Toffoli gate using the following diagram (found in the qiskit textbook):

So, I set V := Rx(pi/2) (as shown in the following diagram) (Note: that I am switching now to the little-endian format)

However, the unitary matrix equivalent to the previous was

$$
begin{pmatrix}
1 & 0 & 0 & 0 & 0 & 0 & 0 & 0\
0 & 1 & 0 & 0 & 0 & 0 & 0 & 0\
0 & 0 & 1 & 0 & 0 & 0 & 0 & 0\
0 & 0 & 0 & 1 & 0 & 0 & 0 & 0\
0 & 0 & 0 & 0 & 1 & 0 & 0 & 0\
0 & 0 & 0 & 0 & 0 & 1 & 0 & 0\
0 & 0 & 0 & 0 & 0 & 0 & 0 & -i\
0 & 0 & 0 & 0 & 0 & 0 & -i & 0\
end{pmatrix}
$$

That will lead to a relative phase of $(-i)$ in the states $lvert 110 rangle$ and $lvert 111 rangle$

What is the reason for that?