I happened to see a young slave, a Greek, who might have been Numantina's male twin.

In support they cite their study of male twins.

The other vampire could have been her male twin.

As useless to him, or to any man, as its male twin was to Lanfear.

The male twin is largely unaffected by the fusion, although the size of the testicles may be slightly reduced.

And standing beside my sister was what looked like her male twin.

Leto, the male twin, was dead, killed by an assassin-tiger.

With this one, I can touch its male twin.

It was like looking at a male twin of Rowan!

Among male identical twins, when one brother had Alzheimer's disease, the other developed the disease 45% of the time.