The accused (29) is charged with 13 offences against the two children on dates in 2018.
The accused (29) appeared in Dublin District Court following extradition from the UK, charged with repeatedly assaulting, ill-treating and endangering the girl and a boy.
Judge Patricia Cronin remanded him in custody after he made no bail application and told the court he was legally representing himself.
The accused is charged with 13 offences against the two children on dates in 2018.
He is charged with raping and sexually assaulting the girl, and recklessly endangering her by failing to get required medical treatment for injuries to her genital area.
It is alleged he thereby caused or permitted the child to be placed or left in a situation that created a substantial risk to her being a victim of serious harm.
A neglect charge alleges he failed to get medical treatment for a fracture to the girl’s left wrist.
The accused is also charged with assault causing harm to both children, as well as charges of wilfully ill-treating, neglecting, abandoning or assaulting them in a manner likely to cause unnecessary suffering or injury to their health, or seriously to affect their well-being.
Most of the offences are alleged to have happened at unknown locations in Dublin, with some of the cruelty charges at a shopping centre.
Garda Sergeant Diane Swift said she arrested the accused on the tarmac at Dublin Airport on a date last month, after he was extradited from the UK on foot of 14 arrest warrants.
She brought him to a Dublin garda station where he made no reply to any of the charges after caution.
Sgt Swift said she was objecting to bail but the accused told the court: “I don’t wish to apply for bail.”
He also declined legal aid.
“I’m a not a guilty man, I don’t need legal representation, I just want to clear my name,” he said.
Asking what prison he would be remanded to, the man said “I’m walking around in fear of my life constantly now, with all these charges. A lot of people are after me.”
He was remanded in custody to appear in Cloverhill District Court.