It wasn't that Angemon was male that gave him second thoughts; it was that he was a digimon. An angel, to be sure, with soft wings that had made an excellent pillow and a humanoid body otherwise, but still a digimon who hatched out of an egg and metamorphosized four times to reach adulthood.
But it was Angemon. Angemon, who he feared losing every time they went into battle, even though the threats these days were nothing compared to Belial Vamdemon – far more than he feared losing himself, even though Angemon was a warrior digimon and Takeru a glorified battery. It was not losing any of his chosen comrades to the darkness which he feared – not his brother, not Hikari, not any of the others who had spent so long by his side – but losing Angemon.
He had talked with Hikari about the issue; the thought horrified her, as much from jealousy as out of her beliefs in the sanctity of same-species love and her memories of the Dark Ocean. But he didn't care. He didn't believe in it in principle, and he wasn't willing to face scandal by advertising that they were more than human and digimon partners. But he didn't feel any need to let the world know to begin with.
Because even if he was supposedly the child of Hope, he was in truth no more optimistic than his brother was a perfect friend. Because as long as Angemon smiled down at him, he could believe in a better future. Because if he was with Angemon, nothing else mattered.