I'm improving relationship with roommate day by day as guide says but still can't get second heart
ps: even with console I'm not able too get it
cousin.heart = 20 but nothin happened :/
It's hard to know what's happening in your game without seeing it myself or checking your saves. However from what you describe it looks like the number of hearts in UI might be also depend on other variables set by progressing the game normally. Try progressing the story and see if you can increase her hearts. The guide is kind of hard to follow because it isn't a true walk-through. The Guide section and the Gallery section tell you what needed to progress the characters and unlocked gallery pictures but not a step by step on progressing the story. You just have to do what's available to you at certain points in the story.
For example you need to do photoshoots with emily before you can do them with roomate. But you need to read photography book have a camera and some costumes before you do the photoshoots with emily (i've gotten softlocked there by not reading the photography book first before doing the photoshoots).
Before you mentioned it I didn't even know about
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. I've been using
Universal Ren'Py Mod for kind of the same thing. Except it allows me to search for variables names/labels/scenes, edit/save variables values as well as play scenes loaded in the Labels tab. I only needed to modify variables twice to unsoftlock the game.