Shy Kitty...Any ideas out there?

Meet LV or Louis, the latest edition to the KL branch. It's been a few weeks since he became part of the family.

Love him to bits, but the problem is that my other cats are still not used to him yet. No fighting instances or anything like that, just that they (the other cats in the house) have not bonded with him yet. He's pretty much of a loner right now and I am afraid that sooner or later it would have an impact on his wee wittle character...Poor poor LV..."Jangan monyok-monyok okiesss???  Mummy loves youuuuuuu..."

Any ideas on how to get them to bond? I've bought toys for them to chase together, put their food at the same area and even put them in the same cage...nothing worked...