Just as no visit to Paris is complete without seeing the Eiffel Tower, you've hardly "done" KL if you haven't seen the Petronas Twin Towers. The magnificent skyscrapers are located at the Kuala Lumpur City Center district, or better known as KLCC and although the whole area is relatively new, as it was developed in the late 90s, it has become an integral and most symbolic part of the Malaysian capital.
There are a few hotels within walking distance to one of the best Kuala Lumpur districts, such as the Mandarin Oriental and Traders Hotel, so accommodation shouldn't be a problem. KLCC is known as a city within a city. Apart from the twin towers, your host can take you shopping at Suria KLCC, visit a public park and a mosque that are open for visitors, and see amazing marine wildlife at Aquaria!