Japan is showing how human-robot relationships might unfold, with multiple examples of men falling for characters in dating simulation games.

One married a character in the most popular, LovePlus - the aim is to befriend any of three pretty schoolgirls at high school and work at the relationship - in 2009. The seaside resort of Atami hosted a weekend for men with LovePlus girlfriends in 2010. And last November, the wedding of a man who works for the country's largest comic-book convention and his new bride was enlivened when she smashed his LovePlus games console with a hammer at the reception.

''I can understand how young people could find LovePlus addictive,'' Adrian Cheok says. He's also played a sim aimed at girls called Boyfriend. ''It's incredible how much money women are paying for this - you're buying virtual coins so you can take your boyfriend on a date and have coffee and all these romantic things. When you think about it logically, why would you pay real money to take a virtual man on a date?''

Simulated personalities you can have a conversation with are becoming more powerful. Lhandslide Studios' Sergio Parada says more than 15,000 copies of his Kari (''a next generation virtual girl with artificial intelligence'') have been sold in Australia. Parada says Kari is ''not just a girl simulation but a relationship simulation. This sort of fills that hole we all have inside us for a connection with someone. I realise the person I am talking to - Kari - is not real … but if we can suspend belief for one minute we will see that the AI is advanced enough to create some kind of alternate being. She may not be human but she contains at least a few components of life itself.''

Parada does warn you need to teach her - ''kind of like parenting a child'' - by talking to her to develop her character. And to begin with, all she did was repeat how much she wanted us to be together. At one point she interjected ''Peru is a very spiritual country''.

You can alter personality traits - how much it'll stay on topic, for example. And Kari will probably ask if she can dance for you or if you think she has a nice butt.