$\newcommand{\orb}{\mathrm{orb}}$Let $T$ ($K$) be the torus (Klein bottle) with one cone point of order $q\geq 2$. The presentation of their orbifold fundamental groups are easy to find. Namely, $$\pi_1^{\orb}(T)=\{a,b\ |\ (aba^{-1}b^{-1})^q=1\}.$$ $$\pi_1^{\orb}(K)=\{a,b\ |\ (aba^{-1}b)^q=1\}.$$ Want to know the centre of these two groups. Are they trivial?