Ah okay thanks @ladynadiad - I couldn't understand why I didn't get the trophy as I did have the guys maxed, but I had missed out the fact that that you also have to NOT spend time with the girls. And I didn't realise I had to take Celine and Spoiler both for a ride despite the fact the fact that Spoiler was maxed.
Thanks all!
There is one trophy for deepening a bond with the guys, and one for Celine and
How are they obtained, cause maxing their bonding stars aren't enough, and one can't make a date with them like with Laura/Alyssa/etc.